13A1. General. Extreme vigilance and care
are necessary in the inspection, cleaning, and
repair of parts. Personnel performing repair
work should use common sense in judging
whether or not a part should be put back into
service or discarded. If there is any doubt,
the part should be replaced. With the exception of the bearings and electrical equipment,
corrosion should be removed from the parts
by washing them in kerosene. Hydraulic
equipment should be washed in clean fresh
water. After cleaning, dry the parts thoroughly, and apply a light film of gyro oil to
prevent rusting or corrosion of the parts.
Use Navy-approved cleaning fluid to clean
grease and oil from the parts. Keep the bearings oiled and clean by wrapping them in wax
paper until they are needed for assembly.
Clean the contacts and slip rings with ordinary paper to remove any film of oil or grease.
Smooth off pitted contacts with a jeweler's
file and polish with a burnishing tool. Do not
use crocus cloth, crocus paper, or sandpaper
on the contacts. Replace all cracked or broken
parts. The area in which repair work is being
done should be kept clean to prevent dust and
dirt from getting on the parts.
13A2. Operating the system on a static head.
This is a means of checking the operation of
Figure 13-1. Maneuvering cocks and drain cocks
positioned for operating on static head.
the log system while the ship is at rest on the
surface. By shutting off the pressure on one
side of the bellows, unequal pressure is obtained on the bellows, and the system will
operate at one speed in the same manner as if
the ship were underway. This permits the
checking and inspection of the system under
operating conditions. The log is operated on
the static head as follows: Turn the valves
to the static head operating position as shown
in Figure 13-1. The system will now operate
at approximately 5 knots. After inspection,
turn the valves to their secured position as
shown in Figure 11-2. The transmitter indicator mechanism will then stop operating and
the speed pointers should be at the zero
position.
Figure 13-2. Maneuvering cocks and drain cocks
in zero position.
13A3. Checking the operation of the system
with a weight and arm. This operation is a
means of checking the functioning of the
system when the ship is either at rest or underway, on the surface or submerged. It is described in detail in Section 14A10.
13A4. Setting the C-adjustment. (See Figures 13-2 and 13-3.) The C-adjustment mechanism consists of a micrometer assembly
which connects the bellows rod with the main
balance arm. This micrometer is a means of
133
Figure 13-3. C-adjustment assembly.
Figure 13-4. Maneuvering cocks and drain cocks
positioned to check for clogged rodmeter.
Figure 13-5. Maneuvering cocks and drain cocks
positioned for blowing out static line.
134
adjusting the master transmitter indicator so
that the speed pointer will point at exact zero
on the dial. Setting the C-adjustment is accomplished in the following manner: Set the
valves to the zero position as shown in Figure
13-2. Thoroughly vent the hydraulic system
as described in Section 11A5. If the speed
Figure 13-6. Maneuvering cocks and drain cocks
positioned for blowing out dynamic line.
pointer is not at the zero position on the dial,
turn the micrometer thimble (shown in Figure
13-3) until the pointer is at exact zero position on the dial. This adjustment is important
because all other log adjustments are performed only after making certain that the
C-adjustment is correct.
Figure 13-7. Maneuvering cocks and drain cocks
positioned for blowing out both hydraulic lines.
B. MAINTENANCE OF RODMETER
13B1. Testing for obstruction in the rodmeter. The rodmeter may become clogged
with jellyfish, mud, seaweed, or other foreign
matter. Consequently the pressure difference
will not be normal, and the mechanism will
not register correctly. The following test
must be performed when the ship is on the
surface. Position the valves and vent cocks
as shown in Figure 13-4. If a full stream of
water does not flow from both drain cocks,
it is an indication that the line not flowing
is clogged.
13B2. Blowing out the rodmeter. This operation should be performed with the rodmeter
in its extended, or operating, position. It is
good practice to blow out both lines even if
the tests for obstruction indicate that only
one line is clogged, as foreign matter has
probably entered both passages. Blow out the
static line in the following manner: Position
the maneuvering cocks and drain cocks as
shown in Figure 13-5. Disconnect the dynamic
line at the pressure snubber as shown in Figure 13-5 and plug the line openings with
rubber corks. Apply low-pressure air to the
fitting at the drain maneuvering cock. After
the static line is blown clear, remove the rubber corks and reconnect the dynamic line.
Blow out the dynamic line as follows: Position the maneuvering cocks and drain cocks
as shown in Figure 13-6. Apply low-pressure
air to the fitting at the drain maneuvering
cock. To blow out both the static and dynamic
lines simultaneously, position the maneuvering cocks and drain cocks as shown in Figure
13-7. Apply low-pressure air to the fitting at
the drain maneuvering cock. After blowing
out the hydraulic lines, test for obstructions
in the rodmeter as described in Section 13B1.
Vent the hydraulic system thoroughly after
blowing out the rodmeter as described in
Section 11A5.
13B3. Removing solid obstructions from the
rodmeter. (See Figure 13-8.) If obstructions
cannot be removed by blowing out the rodmeter with compressed air, the following
operations are necessary: Raise the rodmeter
to its fully housed position. Close the sea
135
valve. Raise the rodmeter until its lower end
is above the sea valve extension. Using a soft
brass wire, dig out the obstructions from the
openings on the lower end of the rodmeter.
Do not use steel wire or a drill to clean out
the openings as they may score the openings,
or break off in the passages. Blow out the rodmeter as described in Section 13B2; in this
case, however, the rodmeter need not be extended into the sea. Have a crew member hold
his hand near the rodmeter openings to detect
the flow of air which indicates that the opening and tubing are clear. Repeat this operation until all the passages are clear.
Align the lower end of the rodmeter with
the opening in the sea valve extension, and
carefully lower the rodmeter to its fully
housed position. Care should be exercised in
lowering the tip of the rodmeter through the
packing gland so that the packing will not be
pushed out of the gland. At the fully housed
position the tip of the rodmeter is approximately 1 inch above the sea valve gate. Open
the sea valve. Place the hoist stop bracket in
its original position above the rodmeter. It is
important that the stop bracket be in position
above the rodmeter at all times, except while
performing the above operation, or when the
rodmeter is being replaced. Lower the rodmeter either to its normally housed position
or to its fully extended position. Place the
hoist crank in the brackets provided, and replace the deck plate over the sea valve.
Figure 13-8. Rodmeter and hoist.
136
C. REPLACING DAMAGED RODMETER
13C1. General instructions. If the rodmeter
is bent so that it cannot be drawn up into the
ship, it will be necessary to install a spare
rodmeter. Do not attempt to force the damaged rodmeter up into the ship, as the hoist
mechanism may be damaged. The removal and
installation operations should be carried out
only when the ship is surfaced. If the damaged rodmeter is to be salvaged, it may be
accomplished if a diver is available. Lower
the diver over the side of the ship so that he
can rig a line around the damaged rodmeter.
Secure the opposite end of the line to the ship
Figure 13-9. Bendix rodmeter.
so that the rodmeter may be pulled out of the
water after it is pushed out of the sea valve.
13C2. Breaking out the spare rodmeter.
Break out the spare rodmeter and place it
alongside of the hoist mechanism so that it
will be immediately available when needed.
13C3. Removing the strap and handle assembly. (See Figure 13-9.) Loosen the hose
clamps and remove the two lengths of hose
from the nipples on the upper end of the rodmeter. Remove the nipples from the rodmeter
and plug the tapped openings with wooden
plugs or standard 1/8-inch pipe plugs. Disconnect the hoist chain link from the rodmeter. Remove the two nuts and bolts that
secure the straps and handle to the rodmeter
and remove the straps and handle. Raise the
hoist chain until the connecting link is in its
topmost position against the stop bracket
above the rodmeter (Figure 13-8).
13C4. Installing the spare rodmeter. (See
Figure 13-9.) The spare rodmeter is equipped
with straps and handle. If the damaged rodmeter is partially raised, push it downward
until the dowel pins rest on top of the packing gland on the sea valve extension. Remove
the two pipe plugs from the spare rodmeter
and install the hose fittings. Connect the hose
to the spare rodmeter and tighten the hose
clamps securely. Place the tip of the spare
rodmeter on top of the damaged rodmeter.
Drive out the dowel pins from the damaged
rodmeter. Push downward on the spare rodmeter until it is completely free of the ship.
Connect the link on the chain hoist to the
rodmeter handle. Vent the hydraulic system
in accordance with the instructions given in
Section 11A5.
D. MAINTENANCE OF PRESSURE BELLOWS
13D1. General. The submarine bellows are
matched as to spring-rate at the factory and
should not be disassembled. The three sections of the bellows assembly (Figure 13-10)
should be replaced as a unit.
13D2. Removing the bellows chamber. (See
Figure 13-11.) Remove the master transmitter
indicator cover retaining screws and cover.
With the rodmeter in its housed position, turn
the valves and maneuvering cocks to the drain
position (Figure 11-6). Spread the ends of the
scissors spring to disengage the spring from
the micrometer and pivot, and remove the
scissors spring. Remove the snap rings from
137
Figure 13-10. Cutaway of bellows assembly.
138
1. SPRING ARM GUIDE
2. MAIN BALANCE ARM PIVOT
3. MICROMETER PIVOT
4. MICROMETER CENTER SCREW
5. LOCK NUT
6. UPPER BEARING HOUSING
7. COUNTERWEIGHT BRACKET
8. BELLOWS ASSEMBLY
9. ROTATING COUNTERWEIGHT
10. SNAP RING
11. COUNTERWEIGHT SHAFT
12. MICROMETER THIMBLE
13. MICROMETER BARREL
14. SCISSORS SPRING ASSEMBLY Figure 13-11. Bellows installation on master
transmitter case.
each end of the counterweight shaft, and remove the shaft. Lift out the counterweight
and its bracket. Do not disturb, in any way,
the counterweight mounted on the bottom of
the main balance arm. Carefully block or hold
the bellows chamber in place while removing
the nuts from the bellows mounting studs.
Carefully lower the bellows assembly from
the master transmitter case.
13D3. Removing the bellows from the chamber. (See Figures 13-12, 13-13, and 13-14.)
Unscrew and remove the bellows chamber
cap. The cap spacer and caution plate are removed with the chamber cap. Loosen the setscrew in the compensating spring holder and
unscrew (counterclockwise) and remove the
spring holder. Carefully remove the compensating spring assembly from the compensating
spring bushing. The spring bushing is removed
after the drain screw is removed. Remove the drain screw and gasket from the
lower end of the drain tube. Loosen the three
setscrews on the compensating spring bushing
and remove the bushing from the drain tube.
Using the special bellows wrench, which is
stowed in the spare parts box, hold the lower
end of the bellows as shown in Figure 13-13.
Unscrew and remove the lock nut that secures
the lower end of the bellows assembly to the
bellows chamber. Unscrew the unions that
secure the maneuvering cocks assembly to the
bellows chamber and place the assembly to
one side. Unscrew and remove the C-adjustment mechanism from the bellows rod by holding the rod with a wrench and unscrewing
the micrometer center screw from the rod.
The counterweight bearing is removed with
the C-adjustment assembly. Remove the lock
nut that secures the upper end of the bellows
assembly to the chamber cover in the same
manner that the bellows lower lock nut was
removed. Loosen the three setscrews that secure the main counterweight support in position on the upper end of the bellows assembly
and unscrew and remove the main counterweight support from the bellows. Remove the
chamber cover by removing the eight cap
screws and lock washers that secure the cover
to the chamber. Lift the bellows assembly out
of the bellows chamber. The bellows may be
stuck in the chamber. If it is, the application
of low-pressure air to the dynamic opening
in the chamber will facilitate its removal.
13D4. Installing the bellows assembly in the
chamber. (See Figures 13-12, 13-13, and 1314.) Make certain that the bellows chamber
gasket is installed on the upper end of the
chamber. Carefully insert the bellows into the
chamber. Secure the lower end of the bellows
to the chamber with the lock nut as follows
Tighten the lock nut in position by holding the lower end of the bellows with the
special spanner wrench as shown in Figure
13-13, while turning up the nut. Place the
bellows chamber cover gaskets in position on
the chamber cover. Carefully place the chamber cover over the threaded end of the bellows
so as not to burr the threads. Align the two
large pipeline openings in the cover and in the
139
Figure, 13-12. Bellows assembly removed.
140
Figure 13-13. Removing bellows lower lock nut.
chamber so that the large openings are on the
same side of the chamber. Align the mounting
holes and install the eight cover retaining
screws and lock washers. Install the lock nut
that secures the upper end of the bellows to
the chamber cover. Temporarily install the
main counterweight bracket and bearing assembly on the upper end of the bellows
assembly.
Do not tighten the setscrews in the counterweight bracket and bearing assembly at
this time, as a final adjustment of the positioning of the assembly must be made when the
bellows assembly is installed on the master
transmitter indicator case.
Place the upper bearing housing assembly
on top of the bellows rod with the large flange
end of the bearing housing toward the top of
the bellows rod. Temporarily install the C-adjustment mechanism in the top of the bellows rod by turning the micrometer center
screw into the rod. Do not tighten the lock
nut on the micrometer center screw or position the micrometer thimble at this time, as a
final adjustment must be made when the complete bellows assembly is installed on the bottom of the master transmitter indicator case.
13D5. Installing the bellows assembly on the
master transmitter case. (See Figure 13-11.)
Position the micrometer thimble of the C-adjustment mechanism in its approximate
central position on the micrometer barrel.
This is done so that the thimble can be moved
in either direction when making the final
zero adjustment. Make certain that the bellows stud gaskets are in good condition and
are installed on the studs. Lift the bellows
assembly into position on the bottom of the
transmitter case. Hold the bellows assembly
in this position while adjusting the micrometer screw in the top of the bellows rod so
that the pivot on top of the micrometer will
just clear the pivot recess in the main balance
arm pivot when the rubber stud gaskets are
compressed. Tighten the lock nuts on the
bellows mounting studs so that the rubber
stud gaskets are completely compressed and
a metal-to-metal contact is obtained between
the bellows chamber cover and the transmitter case. Secure the micrometer center screw
in position by tightening the lock nut on the
center screw up against the inner race of the
counterweight bearing. Install the scissors
spring assembly to hold the micrometer up
against the main balance arm pivot. Apply a
coating of white lead compound to the
threads of the maneuvering and drain cocks.
Install the two unions connecting the maneuvering cocks with the two large tapped openings, one in the chamber cover and one in the
bellows chamber. Tighten the connections.
Install the two drain cocks, one in the cover
and the other in the chamber. Tighten the
connections. Install the drain tubing in the
drain cocks. Place the rotating counterweight
in position on the counterweight support, and
install the counterweight shaft and the two
snap rings that secure the weight to the support. There should be approximately 1/32-inch clearance between the arms of the counterweight and the counterweight bearing.
Check the clearance of the counterweight to
see that it does not touch the case, the weight
on the main balance arm, or any stud. Position
the counterweight for proper clearance by
screwing the counterweight support upward
or downward as necessary. When the proper
clearance is obtained, secure the counterweight support in position by tightening the
setscrews provided in the support. The setscrew should not be made extremely tight,
as the threads on the upper end of the
bellows assembly will be damaged. There are
three setscrews provided in the main counterweight support. It is necessary to tighten only
the most accessible setscrew. Fill the hydraulic system with water. (See Section
11A8.) Vent the system thoroughly. (See
Section 11A5.) Energize the system by turning
on the switches in the control room. Make
the C-adjustment by turning the micrometer
thimble upward or downward until the pointer reads zero on the speed dial. (See Section
13A4.) Check the system for dive error. (See
Section 13E2.)
E. COMPENSATION OF SUBMARINE BELLOWS FOR DIVE ERROR
13E1 General. The submarine bellows is
carefully adjusted for dive error when the
bellows assembly is made at the factory. This
adjustment should not be tampered with
d. The submarine dives to approximately 300 feet. If the log still reads zero knots,
there is no diving error and the system can
be put into operation without further
Figure 13-15. Dive error compensating mechanism.
unless the bellows has been damaged, and the
replacement of the bellows assembly becomes
necessary.
13E2. Checking the system for dive error.
The following operations are necessary in
checking the system for dive error:
a. The system is completely filled with
water and bled of air.
b. The valves and vent cocks are set to
the zero position.
c. The C-adjustment of the master transmitter indicator is set so that the speed
pointer reads zero knots.
NOTE: Open slowly Leave open until pressure is dissipated. Zero point with "C" adjustment, then close drain cock as shown. Figure 13-16. Maneuvering cocks and drain cocks
positioned for dive error adjustment.
143
adjustment. However, there usually is a positive error.
13E3. Adjusting for dive error. (See Figures
13-15 and 13-16.) When there is a positive
dive error noted after performing the-operations outlined in Section 13E2, the following
adjustment procedure is necessary:
a. Remove the chamber cap from the
bottom of the bellows housing.
b. Loosen the setscrew on the compensating spring holder and screw up (clockwise) on the compensating spring holder,
thus compressing the compensating spring.
This will increase the error of the pointer
indicator. The spring should be compressed
until the indicated error of the pointer is
about twice the original error.
c. Remove the static pressure in the
following manner: Position the valves and
vent the cocks as shown in Figure 13-16.
Partially open the static drain cock as shown
by the dotted outline in Figure 13-16. The
static drain cock must be opened slowly so
as to remove the pressure gradually. This is
important as the sudden opening of the drain
cock will damage the bellows. After the
pressure has been dissipated, the speed pointer
will drop but will not return to its zero position.
d. Set the speed pointer to the zero position by means of the C-adjustments. See Section 13A4.)
e. Position the valves and vent cocks to
the zero position by turning the static maneuvering cock to the horizontal position as
shown by the dotted lines in Figure 13-16.
The above procedure may have to be repeated
several times by alternately operating the
static maneuvering cock and the static drain
cock until the correct spring pressure balances out the diving error. Then tighten the
setscrew in the compensating spring holder.
f. Install the cap on the lower end of
the bellows assembly. For an example of the
method used in adjusting for dive error, refer to Section 13E4.
13E4. Example of adjusting for dire error.
(See Figure 13-15 and 13-16.) With the maneuvering cocks in zero position, and the
pointer indicating zero knots, the submarine
dives to 300 feet. If the pointer slowly rises
and stops at 1 knot, the adjustment is made
in the following manner:
a. Remove the chamber cap from the
bottom of the bellows housing.
b. Loosen the setscrew securing the
compensating spring holder.
c. Turn the screw holder clockwise (up),
compressing the compensating spring until
the log indicates 2 knots.
d. The static maneuvering cock (Figure
13-16) is closed and the static drain cock
(Figure 13-16) is slowly and only partially
opened. This reduces the pressure within
the bellows chamber to the ship's atmosphere, and the pointer drops to 1.3 knots.
e. By means of the C-adjustment, the
pointer is made to indicate zero knots.
f. The static drain cock is again closed,
and the static maneuvering cock slowly opened. This increases the pressure within the
bellows chamber to the water pressure of the
sea. The pointer now rises to 0.6 knots.
g. The compensating spring is again
compressed until the log indicates 1.2 knots.
h. The static maneuvering cock is closed
and the static drain cock is slowly opened as
before. The pointer drops to 0.7 knots. The
pointer is made to read zero by means of the
C-adjustment.
i. The static drain cock is again closed
and the static maneuvering cock opened to
the sea. The pointer rises to only 0.2 knots.
If the cycle is repeated once more, the diving
error, for all practical purposes, will have
been eliminated.
j. If the log indications should become
negative for increasing pressures, then the
compensating spring is adjusted too tightly,
and must be backed off.
k. After the spring holder has been set
in the proper position, the setscrews are
tightened, thus locking the spring holder
against the dynamic bellows cap. Do not
damage the threads by forcing the setscrews
too tightly.
l. Replace the bellows chamber cap, being
144
sure to insert the caution plate and cap
spacer between the cap and the bellows chamber.
13E5. Alternate method of adjusting for dive
error. If a pressure pump is available, the
bellows can be compensated when the ship
is in port. The pump is connected to the
static maneuvering cock. The maneuvering
cocks are set in the zero position. The pressure should be checked by means of a pressure gage. A pressure of 150 pounds should
be alternately applied and removed, while
the adjustments described in Section 13E4 are
being made.
F. MAINTENANCE OF SPEED AND DISTANCE INDICATOR
13F1. Removing the pointer and dial. (Figures 13-17, 13-18, and 13-19.) Remove the
case cover retaining screws and cover. Remove the three screws and lock washers that
secure the unit to the case, and lift the unit
from the case. Remove the three screws and
lock washers that secure the pointer hub
cover and the pointer to the pointer hub, and
remove the pointer. Remove the three screws
and lock washers that secure the dial assembly to mounting studs, and carefully lift the
dial assembly off the studs. The deflector
Figure 13-17. Speed and distance indicator removed from case.
145
Figure 13-18. Rear view of speed and distance indicator.
assembly, ringlight sectors, and lamp sockets
are removed with the dial.
13F2. Installing the dial and pointer. (See
Figures 13-19 and 13-17.) Place the dial assembly in position on the dial mounting
studs, and secure it with the three screws
and lock washers provided. Place the pointer
and pointer hub cover in position on the
pointer hub, and secure with the three screws
and lock washers provided. The pointer may
be positioned in reference to the zero mark
on the dial by loosening the pointer retaining
screws and shifting the pointer to the desired
location. Place the instrument in the case
and secure with the three screws and lock
washers provided. Place the case cover in
position on the case and install the cover retaining screws.
13F3. Removing the deflector assembly.
(See Figures 13-17 and 13-19.) Remove the
cover from the case. Remove the four flathead machine screws that secure the deflector
assembly to the ringlight sectors, and remove
the deflector assembly.
13F4. Installing the deflector assembly.
(See Figures 13-17 and 13-19.) Carefully
146
place the deflector assembly in position on
the ringlight sectors, and secure with the
four flathead machine screws provided. Install the case cover.
13F5. Replacing burned-out lamps. (See
Figure 13-19.) Remove the deflector assembly. (See Section 13F3.) Replace the burned out lamps with new lamps. Install the deflector assembly. (See Section 13F4.)
13F6. Removing the ringlight sectors. (See
Figure 13-19.) Remove the dial assembly from
13F4.) Install the dial assembly. (See Section
13F2.)
13F8. Removing the lamp sockets. (See Figure 13-19.) Remove the dial assembly. (See
Section 13FL) Remove the lamps from the
sockets. From the front of the dial remove
the two screws that secure the lamp socket
to the back of the dial. Remove the terminal
screw from the ground wire. Push the center
contact wire forward, unsolder the wire from
the center contact, and remove the wires from
Figure 13-19. Speed and distance indicator, dial removed.
the dial mounting studs. (See Section 13F1.)
Remove the deflector assembly. (See Section
13F3.) From the rear side of the dial remove
the eight screws (two to each sector) that
secure the sectors to the dial, and remove the
sectors.
13F7. Installing the ringlight sectors. (See
Figure 13-19.) Place one of the ringlight
sectors in position on the back of the dial and
secure with the two screws provided. The
other sectors are installed in the same manner.
Install the deflector assembly. (See Section
the socket. Remove the two screws that secure the lamp plate to the lamp bracket, and
pull the socket out of the lamp block. The
other three lamp sockets are removed in the
same manner.
13F9. Installing the lamp sockets. (See Figure 13-19.) Place the socket in the lamp
block. Position the lamp plate and secure it
with the two screws provided. Push the lead
wire into the rear end of the socket and
solder this wire to the center contact. Connect the ground wire to the lamp plate. Place
147
the lamp socket in position and install the
two screws that secure the socket to the dial.
Install the lamp in the socket. The other
three sockets are installed in the same manner. Install the dial assembly. (See Section 13F2.)
13F10. Removing the tap switch. (See Figure 13-19.) Remove the case cover. Remove
the unit from the case. Remove the two
screws that secure the tap switch bracket to
the mounting plate, and carefully pull the tap
switch forward to make the wire connections
accessible. Unsolder and tag the wires for
ready identification. Remove the nut and
toothed lock washer that secure the tap
switch to the tap switch bracket.
13F11. Installing the tap switch. (See Figure 13-19.) Place the new tap switch in position in the tap switch bracket, and secure
with the nut and toothed lock washer provided. Solder the wires to the terminals on the
tap switch. Place the tap switch assembly
in position on the mounting plate and secure
it with the two screws provided. Install the
unit in the case. Install the case cover.
13F12. Removing the distance counter. (See
Figure 13-19.) Remove the dial assembly.
(See Section 13F1.) Remove the four screws
and lock washers that secure the counter to
the front of the main mounting plate, and
remove the counter. The worm gear is
Figure 13-20. Transformer wiring diagram.
removed with the counter assembly. The worm
gear is removed from the countershaft by
loosening the setscrew, knocking out the
tapered pin, and pulling the worm gear off
the countershaft.
13F13. Installing the distance counter. (See
Figure 13-19.) Place the worm gear on the
countershaft and secure it with the setscrew
and tapered pin. Place the counter in position on the front of the mounting plate with
the worm gear and worm properly meshed,
and secure with the four screws provided.
Install the dial assembly. (See Section 13F2.)
13F14. Removing the transformer. (See Figure 13-18.) Remove the dial assembly. (See
Section 13F1.) From the front of the mounting plate remove the two screws that secure
the transformer, to the mounting plate. Unsolder the primary leads from the jack connection. Unsolder the secondary leads from
the tap switch. Tag the tap switch terminals
for ready identification.
13F15. Testing the transformer. (See Figure
13-20.) Connect the two primary leads to the
115-volt a.c. line. Connect a voltmeter across
the secondary leads as shown in Figure 13-20.
Voltage readings should be taken as shown
in Figure 13-20.
13F16. Installing the transformer. (See Figure 13-18.) Place the transformer in position
on the back of the mounting plate, and secure
it with the two screws provided, from the
front of the mounting plate. Solder the two
primary leads to the terminals on the jack
connection. Solder the secondary leads to
the terminals on the tap switch. Install the
dial and pointer. (See Section 13F2.)
13F17. Removing the self-synchronous distance repeater. (See Figures 13-21 and 13-22.)
Remove the unit from its case. Remove the
terminal screws and washers that secure the
lead wires to the distance repeater. Tag the
wires for ready identification. The terminals
are marked S1, S2, S3, R1, and R2. Remove
the three screws and lock washers that secure
the distance repeater motor mounting clamps
to the motor mounting plate, and remove the
repeater from the mounting plate.
13F18. Disassembly of the distance repeater. (See Figure 13-23.) Remove the three
screws that secure the terminal cover to the
terminal ring assembly, and remove the terminal cover. Unsolder the stator leads from
the terminal plates on the terminal ring assembly. Remove the three screws that secure
the terminal ring assembly to the stator housing, and remove the ring assembly. The end
and side contact assemblies are secured in the terminal ring assembly with one screw. Slide
the insulating plate off the wires. Remove
the tapered pin from the front end of the
rotor shaft. This pin engages the slot on the
shaft extension of the worm shaft. Remove
the three screws that secure the end cap assembly to the stator housing, and remove the
end cap assembly. Pull the rotor and damper assembly from the stator housing. Remove the ball bearing and bearing spring from
the front end of the rotor shaft. Using a small
drive punch, drive out the outer race and
shims from the end cap assembly. Holes are
provided in the end cap assembly for the insertion of a drive punch. Remove the shim
and bearing outer race from the back end of
the stator housing in the same manner. Remove the bearing and brass dust guard from
the rear end of the rotor shaft.
13F19. Assembly of the self-synchronous
distance repeater. (See Figure 13-23.) Place
the shim and bearing outer race in the back
1. END CAP SCREW
2. END CAP
3. SHIMS
4. FRONT BEARING
5. ROTOR AND DAMPER, ASSEMBLY
6. REAR BEARING
7. STATOR HOUSING
8. STATOR LEADS
9. TERMINAL RING, ASSEMBLY
10. TERMINAL COVER
11. TERMINAL COVER SCREW
12. TERMINAL RING SCREW
13. INSULATING PLATE
14. REAR BEARING OUT RACE
15. DUST GUARD
16. BEARING SPRING
17. FRONT BEARING OUTER RACE
end of the stator housing, with the flange
end of the race toward the end of the stator
housing. Place the brass dust guard on the
rear end of the rotor shaft, with the shoulder
on the dust guard facing toward the end of
the shaft. Place the ball bearing over the
end of the rotor shaft and against the shoulder on the brass dust guard. Carefully insert
the rotor and damper assembly into the stator housing, being careful to align the bearing in the outer race in the back end of the
stator housing. Place the bearing spring over
the front end of the rotor shaft, with the
large diameter of the spring adjacent to the
damper flywheel. Place the ball bearing
over the front end of the rotor shaft and adjacent to the bearing spring. Place the shims
and bearing outer race in the end cap assembly. Install the end cap assembly over the
front end of the rotor shaft, and up against
the stator housing. Secure the end cap with
the three screws provided. Place the insulating plate over the stator leads, with the
smooth side of the plate adjacent to the stator
housing. Place the terminal ring assembly
over the stator leads and up against the stator
housing. Secure the ring with the three
screws provided. Solder the stator leads to
the terminals on the terminal plates. Install
the terminal cover on the terminal ring with
the three screws. If a new rotor assembly
has been installed, it will be necessary to drill
a pin hole in the front end of the rotor shaft.
Using the old rotor shaft as a guide, measure
the distance from the center of the pin hole to
the end of the rotor shaft in the same manner as shown for the speed repeater in Figure 13-26. Drill a transverse hole using a
No. 55 drill for a 5/16-inch X 0.052 inch stainless steel pin. Press the pin into the hole in
the rotor shaft. It is not necessary to set the
distance repeater to electrical zero.
13F20. Installing. The self-synchronous distance repeater. (See Figure 13-21.) Connect
the stator and rotor lead wires to the terminal
ring of the distance repeater. Tighten the
terminal screws securely. Align the pin on
the front end of the rotor shaft with the slot
provided in the worm shaft extension, and
place the distance repeater in position on the
mounting plate. Secure the repeater with the
three clamps and the three clamp screws provided. Install the unit in the case.
13F21. Removal of the self-synchronous
speed repeater. (See Figure 13-18.) Remove
the interior unit from the case. Remove the
terminal block cover retaining screws and
cover. The terminal block outer cover plate
is removed with the terminal block cover.
Cut the string that secures the lead wires
together in order to fan out the lead wires
near the terminals. Make a note of the position of the end contact terminal. This is the
R1 lead terminal. Progressing in a counterclockwise direction, the other two brush terminals are identified as the R2 terminal and
the R3 brush terminal. The wires are tagged
with metal tags. The stator lead S2 is connected to the upper stator terminal, and the
stator lead S1 is connected to the lower stator
terminal. Remove the terminal screws that
secure the leads to the terminal block, and
1. CONTACT PLATE
2. TAPPED SIDE CONTACT CLAMP PLATE
3. SIDE CONTACT SPRING
4. SIDE CONTACT CLAMP PLATE
5. LOCK WASHER
6. SIDE CONTACT SCREW
7. CONTACT TENSION SPRING
8. CONTACT SPRING BRACKET
9. END CONTACT CLAMP PLATE
10. TERMINAL BLOCK
11. TERMINAL PLATE
12. END CONTACT SPRING
13. END CONTACT SCREW Figure 13-24. Terminal block assembly
partially disassembled.
151
remove the leads from the terminals. Cut off
the terminal lugs from the ends of the rotor
leads in order that these wires can be pulled
out of the holes provided in the terminal
block. Remove the three clamp screws and
clamps that secure the speed repeater to the
mounting plate, and remove the speed repeater.
13F22. Removing the contact assembly. The
contact assembly can be removed from the
speed repeater as a unit. Remove the terminal block cover retaining screw and the
terminal block cover. Disconnect the rotor
and stator lead wires from the terminal block
as described in Section 13F21. Remove the
two screws and lock washers that secure the
terminal block to the rear end cap. Cut off
the terminal lugs from the two stator leads
that connect the stator with the contact
plates. This is necessary in order that these
two wires may be pulled through the holes
provided in the terminal block. Remove the
terminal block from the rear end cap.
13F23. Removing the contacts. (See Figure
13-24.) Support the front end of the speed
repeater on wooden blocks so that the terminal block is in an upright position. Remove
the end contact assembly in the following
manner: Remove the two screws and lock
washers that secure the contact clamp plate,
contact spring, and contact spring bracket to
the contact plate. Remove the parts from
the terminal block with tweezers. Remove
the side contact assemblies in the following
manner: Remove the two screws and lock
washers that secure the side contact clamp
plates and the side contact spring to the
contact plate, and carefully remove the parts
with tweezers. The second side contact assembly is removed in the same manner.
13F24. Cleaning the contacts and slip ring.
Clean the contacts and the slip ring with a
clean piece of note paper. Smooth the pitted
contacts with a jeweler's file, and polish the
surfaces with a burnishing tool. Do not; use
emery cloth or crocus paper as fine particles
from the cloth or paper will become imbedded in the soft metal of the contacts and slip
ring.
13F25. Installing the contacts. (See Figure
13-24.) Install one of the side contact assemblies in the following manner: Using
tweezers, align one contact spring and the
two contact clamp plates with the contact
plate. Install the two screws and lock washers that secure the spring and clamp plates
to the contact plate. The second side contact spring is installed in the same manner.
Install the end contact assembly as follows:
Align the contact spring bracket, contact
spring, and contact clamp plate with the end
spring contact plate, and install the two
screws and lock washers that secure the end
spring contact in position on the contact
plate.
13F26. Installing the contact assembly. (See
Figure 13-25.) Insert the two stator wires
through the holes provided in the terminal
block. These are the two holes nearest the
outer circumference of the terminal block.
Be careful not to bend the contact springs.
Secure the terminal block to the rear end
cap with the two screws provided. Solder the
terminal lugs on the ends of the two leads
from the stator, and connect these wires to
the contact plate with the screws and lock
washers provided. Connect the S1 lead to
the lower stator terminal, and the S2 lead to
the upper stator terminal. Insert the R1
lead through the lower hole provided in the
terminal block, the R2 lead through the upper
hole, and the R3 lead through the center
hole. Solder the terminal lugs on the ends
of these rotor leads. Connect these rotor
leads to the contact plates. Place the terminal
block outer cover plate in position on the
terminal block, and install the terminal block
cover on the terminal block. Secure the cover
with one screw. Install the unit in its case.
13F27. Removing the speed repeater rotor
and bearings. (See Figure 13-25.) Remove the
self-synchronous speed repeater. (See Section 13F21.) Remove the terminal block. (See
Section 13F22.) Lift off the terminal block
center cover plate and the terminal block inner cover plate. The two terminal lead insulating bushings are removed with the terminal block inner cover plate. Scribe a locating mark on the rear end cap and on the
152
1. END CAP SCREW
2. LOCK WASHER
3. FRONT END CAP
4. SHIMS
5. BEARING SPRING
6. BEARING OUTER RACE
7. FRONT BEARING
8. BEARING INNER RACE
9. DUST GUARD
10. ROTOR AND DAMPER ASSEMBLY
11. STATOR SHELL
adjacent stator shell so that the end cap can
be installed in the same relative position at
assembly. Remove the three rear end cap
retaining screws and lock washers, and remove the rear end cap. The rear bearing
outer race and shim are removed with the
rear end cap. Remove the setscrew that secures the pointer hub to the rotor shaft, and
remove the pointer hub. Remove the three
front end cap retaining screws and lock washers, and remove the front end cap. Be careful
not to lose the bearing outer race, bearing
spring, and shim from the front end cap. Remove the rotor and damper assembly from
the stator shell. Remove the bearing, bearing inner race, and dust guard from the front
end of the rotor shaft. Remove the rear
bearing, bearing inner race, and dust guard
from the rear end of the rotor shaft. Remove
the front bearing outer race, bearing spring,
and shims from the front end cap. Remove
the rear bearing outer race and shim from
the rear end cap. The outer race and shim are
removed from the rear end cap by inserting a
small drive punch through holes in the rear
end cap and driving out the shim and outer
race.
13F28. Assembling the self-synchronous
speed repeater. (See Figure 13-25.) Place the
rear bearing dust guard on the rear end of
the rotor shaft, with the shoulder on the guard
facing away from the rotor. Place the bearing inner race on the rear end of the rotor
shaft adjacent to the dust guard. Place the
shim and outer bearing race in the rear end
cap with the flange of the race toward the cap.
The race is a light press fit into the end
cap. Place the rear ball bearing on the rear
bearing inner race. Install the rear end cap
on the stator shell with the locating scribed
marks aligned. Secure the rear end cap with
the three screws and lock washers provided.
Carefully install the rotor and damper assembly into the stator shell, making certain
that the rear end of the stator shaft is aligned
with the opening in the rear end cover. Support the rear end cover and stator shell on
wooden blocks in order to assemble the front
end of the repeater. Place the front bearing
dust guard over the front end of the rotor
shaft, with the shoulder of the guard away
from the rotor. Install the front bearing inner race adjacent to the front bearing dust
guard. Place the ball bearing on the inner
153
race on the front end of the rotor shaft. Install the shims, bearing spring, and outer
race in the opening provided in the front end
cap. The lugs of the bearing spring should
face the rotor, and the flange of the outer
race should face the end cap. Install the front
end cap on the stator shell, being careful
when inserting the rotor shaft through the
end cap not to damage the bearing. Secure
the front end cap with the three screws and
lock washers provided. Turn the rotor shaft
by hand to make sure that the rotor rotates
freely. Turn the repeater over so that the
front end cap rests on wooden blocks on the
bench. Place the two lead insulating bushings over the stator leads, with the flange
end of the bushings away from the end cap.
Insert the bushings into holes provided in
the rear end cap. Install the terminal block
inner cover plate on the rear end cap by inserting the stator leads through the large
holes in the inner cover. Place the terminal
block center cover plate over the slip rings
and against the rear end cap. Install the terminal block. (See Section 13F26.)
13F29. Installing the self-synchronous speed
repeater. (See Figures 13-18, 13-25, and 13-26.)
Align the scribe mark on the front end cap
with the scribe line on the back of the mounting plate, and place the repeater in position
on the back of the mounting plate. Secure in
position with the three clamps and clamp
screws provided. If a new rotor has been
Figure 13-26. Locating position of pointer hub
handle screw.
installed it will be necessary to drill a new
pointer hub screw hole in the new shaft.
Locate and drill the hole in the following
manner: Measure the distance of the centerline of the hole from the front end of the
old rotor shaft as shown in Figure 13-26.
Mark the location of the hole and drill a hole
in the new shaft, using a No. 32 drill. Tap
a bole for a 6-40 screw. Install the pointer
hub on the shaft and secure with the screw
provided. Install the dial and pointer. (See
Section 13F2.) Set the speed repeater to
electrical zero. (See Section 13F30.)
13F30. Setting the speed repeater to electrical zero. (See Figure 13-27.) Set the speed
Figure 13-27. Wiring diagram showing connections
for setting speed repeater to electrical zero.
repeater to electrical zero as follows: Contact the terminals of the speed repeater S1
to R2 to one side of the line. Connect S2 to
R1 and R3 to the other side of the line as
shown in Figure 13-27. Energize the unit.
Do not leave the power on for mote than 5
minutes, or the motor will overheat. When
the unit is energized, the shaft will assume a
definite position (zero position). Loosen
the three screws that secure the pointer to
the pointer hub, and shift the pointer to the
zero position on the dial. Lock the pointer in
this position by tightening the three pointer
screws.
13F31. Disassembly of the counter drive
worm assembly. (See Figure 13-28.) Remove
the distance counter. (See Section 13F12.)
Remove the two screws that secure the worm
bracket to the mounting plate. Carefully pry
the worm bracket from the mounting plate.
The bracket is pinned to the mounting plate,
and care should be exercised not to bend the
pins. Drive out the tapered pin that secures
the worm on the shaft. Pull the worm assembly out of the worm bracket. Remove the
outer bearing, dust washer, worm, inner dust
washer, and inner bearing from the worm
shaft. It may be necessary to file off the
burrs from the pin holes in order to remove
the inner bearing.
13F32. Assembly of the counter drive worm
assembly. (See Figure 13-28.) Place the inner
bearing on the worm shaft, with the bearing
shield toward the shaft extension. Install the
inner dust washer on the shaft, with the
shoulder on the washer facing the inner race
of the inner bearing. Place the worm on the
shaft and install the tapered pin that secures
the worm on the shaft. Install the outer
dust washer on the shaft, with the shoulder
on the washer facing the front end of the
shaft. Place the worm and shaft assembly in
the worm bracket. Align the dowel pin holes
of the bracket with the holes provided in the
mounting plate, and install the bracket on
the mounting plate. Secure the bracket to
the mounting plate with the two screws provided. Install the counter. (See Section
13F13.)
G. MAINTENANCE OF MASTER TRANSMITTER INDICATOR
13G1. Removing the unit from the case.
(See Figure 13-29.) Lower the bellows from
the case so that the C-adjustment mechanism
will clear the bottom of the main balance arm.
(See Section 13D2.) Remove the screws that
secure the main mounting plate to the case,
and carefully lift the master transmitter log
mechanism from its case. Place the log mechanism on a bench, or in an inspection stand.
13G2. Replacing the pointer and dial. (See
Figure 13-29.) Remove the screw that secures the pointer and pointer washer to the
pointer hub, and carefully lift the pointer off
the pin of the pointer hub. Mark the back
of the pointer so that it may be installed in
the same relative position. Remove the three
screws that secure the dial to the dial posts,
and remove the dial. Place the new dial in
position on the dial studs and secure with the
three screws provided. Place the pointer and
pointer washer in position on the pointer hub
and secure with the pointer screw provided.
13G3. Removing the follow-up motor. (See
Figure 13-30.) Remove the four screws that
secure the follow-up motor mounting clamp
to the main mounting plate, and lift the motor
to one side so that the lead wires are made
accessible. Unsolder the wires from the
motor terminals, and mark the wires for ready
identification. Place the motor to one side.
13G4. Replacing the follow-up motor. (See
Figures 13-31 and 13-32.) Remove the fan
from the follow-up motor shaft by loosening
the setscrew in the fan hub. Remove the motor mounting clamp from the old motor by
removing the two screws, lock washers, and
spacer washers that secure the clamp to the
motor. Remove the gear assembly from the
old motor by removing the snap ring and lifting the gear assembly from the gear mounting stud of the motor as shown in Figure 13-31. Place the gear assembly on the stud of
7. FOLLOWER
8. ROTATING DISK
9. COMPONENT FRAME ASSEMBLY
10. MAIN MOUNTING PLATE
11. CONTACT ARM
12. CONTACT ASSEMBLY
Figure 13-29. Master transmitter indicator removed from case.
the new motor and secure it with the snap
ring as shown in Figure 13-32. Place the
spacer washers in position on the new motor,
and place the motor mounting bracket on the
spacer washers. Secure the bracket to the
motor with the two screws and lock washers
provided. Place the fan on the motor shaft,
and tighten the setscrews in the fan hub.
13G5. Installing the follow-up motor. (See
Figure 13-30.) Solder the motor lead wires
to the terminals on the motor. Place the
motor and mounting bracket in position on
156
Figure 13-30. Removing follow-up motor.
Figure 13-31. Replacing follow-up motor, Step 1.
157
Figure 13-32. Replacing follow-up motor, Step 2.
Figure 13-33. Rear view of master transmitter indicator.
158
the front of the main mounting plate, and
secure it with the four screws provided.
13G6. Removing the self-synchronous speed
transmitter. (See Figure 13-33.) Remove the
master transmitter indicator mechanism from
the case. Remove the terminal block cover
retaining screw and the terminal block cover.
The terminal block outer cover plate is removed with the terminal block cover. Disconnect the stator and rotor leads in the same
manner as described for the disconnection of
the leads of the speed repeater. (See Section
13F21.) Unsolder and remove the rotor lead
terminal lugs. Pull the wires out of the terminal block. Turn the power motor shaft by
hand so that the gear on the motor speed
transmitter shaft will clear the main cam. Remove the three clamp screws and clamps that
secure the speed transmitter to the main
mounting plate, and carefully remove the
speed transmitter.
13G7. Disassembly of the speed transmitter.
(See Figure 13-34.) Remove the gear from
the front end of the rotor shaft by removing
the handle screw and socket head setscrew
that secure the gear to the shaft. Remove the
front end cap retaining screws, and the front
end cap. Carefully pull the rotor assembly
out of the stator shell. Remove the front end
bearing, bearing inner race, and front bearing dust guard from the front end of the rotor shaft. Remove the outer race and shims
from the front end cap. Unsolder the terminal lugs from the stator inner leads. Remove
the terminal block retaining screws and lock
washers, and remove the terminal block. Remove the terminal block inner and center
cover plates from the rotor shaft. Remove the
terminal lead insulating bushings from the
rear end cap. Remove the rear end cap retaining screws and lock washers, and remove
the rear end cap from the stator shell. Remove the rear ball bearing, ball bearing inner race, and rear bearing dust guard from
the rear end of the rotor shaft. Knock the
rear bearing outer race and shims out of the
rear end cap.
1. SETSCREW.
2. HANDLE SCREW.
3. SPEED TRANSMITTER DRIVEN GEAR.
4. FRONT END CAP SCREW.
5. FRONT END CAP.
6. SHIMS.
7. BEARING OUTER RACE.
8. FRONT BEARING.
9. BEARING INNER RACE.
10. DUST GUARD.
11. ROTOR ASSEMBLY.
12. STATOR SHELL.
13. STATOR LEADS.
14. DUST GUARD.
15. BEARING INNER RACE.
13G8. Assembly of the speed transmitter.
(See Figure 13-34.) Place the shims and
bearing outer race in the rear end cap, with
the flange on the race toward the end cap.
Install the rear end cap on the stator shell
by inserting the stator leads through the end
cap, and secure the end cap to the stator
shell with the four screws provided. Place
the rear bearing dust guard on the rear
end of the rotor shaft with the shoulder
of the guard toward the end of the shaft.
Install the rear bearing inner race and
rear bearing on the rotor shaft. Place the
rotor assembly into the stator shell, being
careful not to damage the bearing as the shaft
is inserted through the rear end cap. Place
the shims and front bearing outer race in the
front end cap, with the flange of the race
toward the end cap. Install the front bearing
dust guard on the shaft, with the shoulder
of the guard facing the end of the shaft. Install the bearing inner race and the front
bearing on the rotor shaft. Install the front
end cap on the stator shell and secure with
the four screws and lock washers provided.
Turn the rotor shaft to make sure that the
shaft is rotating freely. Install the gear on
the front end of the shaft, and secure it with
the handle screw and socket head setscrew.
If a new rotor has been installed, it will be
necessary to drill and tap a hole in the shaft
for the gear screw. (See Section 13G9.) Place
the lead insulating bushings over the stator
leads, and insert the small end of the bushings
into the holes provided in the rear end cap.
Place the terminal block center and inner
cover plates on the rear end cap, with the
stator leads inserted through the holes provided in the inner cover plate. Hold the terminal block in position near the rear end
cap, and insert the stator leads through the
two holes provided nearest the outer circumference of the terminal block. Carefully
spread the side contacts while installing the
terminal block so that the contact springs
will not be bent. Secure the terminal block
to the rear end cap with the two screws and
lock washers provided. Solder the terminal
lugs on the end of the stator inner leads, and
connect the inner lead terminals to the terminal plate located between the stator leads.
Place the speed transmitter in position on
the main mounting plate, and temporarily install the clamps and clamp screws. Do not
tighten the clamp screws at this time, as the
motor will have to be shifted when setting it
to electrical zero. Connect the rotor and
stator leads to the terminal block in the same
manner as described in Section 13F26. Set
the speed transmitter to electrical zero. (See
Section 13G10.)
13G9. Drill and tap rotor shaft. When a new
rotor is installed in the self-synchronous
speed transmitter, it is necessary to drill and
tap a hole in the shaft for installation of the
motor-driven gear. This operation is performed in the following manner: Locate the
position of this hole by measuring the distance from the end of the shaft to the centerline of the hole on the old rotor shaft as
shown in Figure 13-26. Locate the position
of the hole on the new rotor shaft. Using a
No. 29 drill, drill a hole through the shaft.
Tap this hole for an 8-36 screw. Place the
gear on the rotor shaft and secure it with a
handle screw and socket head setscrew. Set
the speed transmitter to electrical zero. (See
Section 13G10.)
13G10. Setting the speed transmitter to electrical zero. Install the dial and pointer. (See
Section 13G2.) The speed pointer should be
set at zero on the dial. While the speed transmitter is temporarily installed on the main
mounting plate, move the transmitter back
so that the gear on the shaft is disengaged
from the gear on the cam and bracket assembly. Use one of the speed and distance indicators (repeaters) as a checking instrument.
Energize the system. Manually turn the speed
transmitter gear until the pointer on the
speed and distance repeater is indicating
zero. Carefully push the speed transmitter
forward until the gears are properly meshed.
Any slight shifting of the speed and distance
repeater pointer is compensated for by a
slight rotation of the speed transmitter stator
shell in the main mounting plate. When the
pointer is at exact electrical zero, tighten the
motor mounting clamps. Place the terminal
block outer cover plate in position on the
terminal block, and install the terminal block
160
cover. Secure the cover with the screw provided. Install the unit in the case.
13G11. Distance transmitter. The self-synchronous distance transmitter of the master
transmitter indicator is removed, disassembled, and assembled in the same manner as
the speed transmitter. (See Sections 13G6,
13G7, and 13G8.) It is not necessary to set
the distance transmitter to electrical zero.
remove it from the differential shaft. The
left-hand friction disk is removed with the
friction disk holder. Remove the clutch
plate, right-hand friction disk, and spring
holder plate from the differential shaft. Drive
out the pin that secures the slipping clutch
compression spring in the spring adjuster,
and remove the spring from the shaft. Loosen
the spring adjuster socket head setscrew,
and remove the spring adjuster. Loosen the
Figure 13-35. Differential assembly removed.
13G12. Removing the differential assembly.
(See Figure 13-35.) Drive out the pin that
secures the universal center in the universal
joint. Move the universal center to the right
and out of the universal joint. Remove the
four screws that secure the differential frame
to the main mounting plate. Carefully remove the differential assembly from the main
mounting plate. The differential frame is
pinned to the mounting plate and must be
carefully pried away from it. The differential assembly is usually replaced as a unit.
In the event that it become necessary to clean
and replace individual parts, the differential
assembly must be disassembled, as described
in Section 13G13.
13G13. Disassembling the differential assembly. (See Figure 13-36.) Loosen the friction disk holder socket head setscrew and
bearing collar setscrew, and remove the bearing collar. Loosen the distance transmitter
drive gear setscrew, and remove the gear from
the shaft. Remove the bearing from the distance transmitter drive gear. Remove the
dust washer from the left-hand side of the
differential frame. Remove the nut, lock
washer, dust washer, and spider bevel gear
from the spider shaft. Remove the bearing from the spider bevel gear.
Loosen the two socket head setscrews in
the differential frame. Push the differential
shaft toward the left, and remove the bearing and bearing spacer from the left side of
the differential frame. Loosen the setscrew
in the differential right-hand gear; then pull
the shaft toward the left in order to remove
the bearing from the right-hand gear. Drive
out the tapered pin from the differential
161
1 FRICTION DISK HOLDER.
2 LEFT HAND FRICTION DISK.
3 CLUTCH PLATE.
4 RIGHT HAND FRICTION DISK.
5 SPRING HOLDER PLATE.
6 COMPRESSION SPRING PIN.
7 SLIPPING CLUTCH COMPRESSION SPRING.
8 SPRING ADJUSTER.
9 BEARING COLLAR.
10 DRIVE GEAR BEARING.
11 DISTANCE TRANSMITTER DRIVE GEAR.
12 DUST WASHER.
13 BEARING.
14 LEFT HAND BEARING SPACER.
15 HOLLOW SHAFT.
16 BEARING.
17 DUST WASHER.
18 LEFT HAND DIFFERENTIAL GEAR.
19 DIFFERENTIAL SHAFT AND SPIDER.
right-hand gear, and remove this gear and
the dust washer from the universal joint.
Pull the universal joint assembly from the
right side of the differential frame; then remove the bearing, bearing inner and outer
spacers, second bearing, and dust washer
from the universal joint. Loosen the differential left-hand bevel gear setscrew, and
remove the gear from the hollow shaft. Push
the hollow shaft assembly out of the left
side of the differential frame. Remove the
dust guard and bearing from the hollow shaft.
Remove the differential right-hand bevel gear
bearing and dust washer from the right end
of the differential shaft. Remove the differential shaft and spider from the differential frame.
13G14. Assembly of the differential assembly. (See Figure 13-36.) Install the bearing
and dust washer, with the shoulder facing
the bearing race, on one end of the differential
hollow shaft. Install the bearing spacer,
second bearing, and dust washer on the opposite end of the hollow shaft in the same
manner. Place the left-hand differential
gear on the long end of the differential shaft,
with the gear teeth facing the spider; then
insert the long end of the shaft through the
left-hand side of the differential frame, from
right to left. Slide the hollow shaft assembly over the long end of shaft and into approximate position in the left-hand side of
the differential frame.
Make certain that the long section of the
hollow shaft is facing the spider, otherwise
the hollow shaft assembly will not line up
properly in the frame.
Install the dust washer on the left-hand
side of the universal joint, with the shoulder
on the dust washer facing away from the
large section of the universal joint. Install
the inner and outer bearing spacers; then
162
install the universal joint left-hand bearing
adjacent to the inner and outer spacers. Install the bearing in the left-hand differential
gear. Hold the left-hand differential gear
in position on the differential frame, and insert the universal joint assembly into the
opening in the right side of the frame and
into the left-hand differential gear. Place
the dust washer on the short end of the differential shaft, with the shoulder of the
washer away from the spider. Push the differential assembly toward the right while
holding the universal joint assembly in position, to engage the differential shaft and
universal joint. Install the bearing in the
spider bevel gear; and place this gear in position on the spider, with the gear teeth meshing with the differential gears. Install the
dust washer on the spider bevel gear, with
shoulder of the washer toward the bearing
race. Install the lock washer and nut that
secure spider bevel gear in position on the
spider.
Align the hole in the right-hand differential gear with the hole in the universal
joint and install the tapered pin that secures
the gear in position on the joint. Tighten the
socket head setscrew in this gear hub. Install
the bearing in the distance transmitter drive
gear and install this gear on the left end of
the hollow shaft, with the gear teeth facing
away from the frame; then tighten the setscrew in the gear hub. Align the gears and
shaft assembly in the differential frame and
tighten the two socket head setscrews that
secure the bearing spacers in the differential
frame. Tighten the setscrew in the left-hand
differential gear hub. Manually turn the
spider and shaft by hand to be sure that the
parts are rotating freely.
Install the dust washer adjacent to the
distance transmitter drive gear with the
shoulder of the washer facing the bearing. Install the bearing collar on the left end of the
shaft, and tighten the collar setscrew. Place
the spring adjuster adjacent to the bearing
collar, and tighten the adjuster setscrew.
Install the slipping clutch compression spring
in the spring adjuster. Compress the spring
and install the pin that secures the spring in
the adjuster. Install the spring holder plate,
with the slot in the plate aligned over the
spring holder pin.
Install the right-hand friction disk, with
the slot in the disk over the spring holder
pin. Install the clutch plate, left-hand friction disk, and friction disk holder on the differential shaft, with the flat on shaft aligned
with the setscrew in the friction disk holder
hub; then tighten the hub setscrew.
13G15. Installing the differential assembly.
(See Figure 13-35.) Place the differential
assembly in approximate position on the
main mounting plate so that the universal
center is inserted within the universal joint.
Use care in aligning the clutch plate with the
rheostat assembly. Align the pin holes in the
main mounting plate with the pins in the
universal frame, and carefully place the universal assembly in exact position on the
mounting plate. Install the four screws that
secure the differential frame to the mounting plate. Install the pin that secures the
universal center in the universal joint.
13G16. Removing the constant speed motor.
(See Figure 13-37.) Remove the log mechanism from its case. Remove the differential
assembly so that the motor mounting screws
are accessible. (See Section 13612.) Loosen
the two setscrews that secure the rotating disk
to the motor shaft. Disconnect and tag the
electrical leads. Remove the two screws and
lock washers that secure the limit switch
assembly to the mounting plate, and swing
the switch assembly out of the way. From
the front of the main mounting plate remove
the four screws and lock washers that secure
the constant speed motor to the mounting
plate. One man holds the disk while a second
man carefully pulls the motor shaft out of
the friction disk. The motor shaft is sometimes burred because the setscrews have been
forced too tightly. In such a case the motor
will have to be turned clockwise and counterclockwise through approximately a 45-degree
arc while pulling it away from the disk. Remove the friction disk. Cut the string that
secures the lead wires to the main leads. Remove the tape from the ends of the leads,
163
Figure 13-37. Constant speed motor removed.
and unsolder the lead connections. Tag the
leads for ready identification. Place the motor
to one side.
13G17. Disassembly of the constant speed
motor. (See Figure 13-38.) Remove the three
reduction gear housing screws, and remove
the housing. Remove the four screws that
secure the motor to the condenser, and lift
the motor to one side of the condenser so
that the end caps may be removed. Remove
the four screws that secure the back end cap
to the motor frame, and remove the end cap. Pull the rotor assembly from the motor frame.
Remove the bearing from the worm gear end
of the rotor shaft. The bearing is a light
press fit. Remove the bearing and shims
from the back end cap.
13G18. Assembly of the constant speed
motor. (See Figure 13-38.) If the felt retainers have been removed for any reason
place a felt washer between the two felt retainers, and place the retainers in position or
the back end cap. Secure the retainers with
the four screws provided. Place the bearing
on the worm end of the rotor shaft, with the
bearing shield toward the shaft end. Place
the shims and bearing in the back end cap
with the bearing shield toward the end, cap
164
Figure 13-38. Constant speed motor partially disassembled.
Place the reduction gear housing in position
on the front end of the motor, and secure
with the three screws provided. Carefully
insert the rotor into the frame with the worm
on the shaft meshed with the gear on the
reduction gear housing. Place the back end
cap in position on the motor frame, being
careful when aligning the rear end of the
rotor shaft with the bearing in the back end
cap. Secure the end cap with the four screws
provided. Place the constant speed motor in
position on the rear of the main mounting
plate, and secure it with the four screws and
lock washers provided. Place the rotating
disk on the motor shaft and secure it with
the two setscrews provided. Place the limit
switch assembly in position on the main
mounting plate and secure it with the two
screws and lock washers provided. Connect
the electrical leads. Install the differential
assembly. (See Section 13G15.)
13G19. Disassembly of the reduction gear
housing. (See Figures 13-38 and 13-39.) Remove the reduction gear housing from the
motor. (See Section 13G17.) Unscrew and
remove the packing nut and three felt washers from the gear housing. Loosen the two
setscrews that secure the worm gear on the
motor shaft, and pull the drive shaft out of the
gear housing. Lift out the worm gear and
spacing bushing from the gear housing.
Unscrew and remove the lock nut from the adjusting screw. Unscrew and remove the adjusting screw, washer, black felt washer, and
thrust disk from the gear housing.
13G20. Assembly of the reduction gear housing. (See Figures 13-38 and 13-39.) Insert the
drive shaft into the packing gland in the reduction gear housing. Place the spacing
bushing and worm gear on the shaft. Align
the holes in the gear hub with the holes in
the shaft, and install and tighten the
two setscrews that secure the worm gear
to the shaft. Install the thrust disk, adjusting screw, black felt washer, plain washer,
adjusting screw, and adjusting screw lock
nut on the opposite end of the gear housing.
Place the three felt washers over the long
end of the drive shaft, and slide the washers
into the packing gland. Install the packing
nut. Install the reduction gear housing on
the motor. (See Section 13G18.)
13G21. Removing the power motor. (See
Figure 13-40.) Tag the electrical leads to
the motor for ready identification. Unsolder
the leads from the motor terminal lugs. Remove the four screws that secure the motor to
the rear side of the mounting plate, and remove the motor.
13G22. Disassembly of the power motor.
(See Figure 13-41.) Knock out the pin and
loosen the setscrews that secure the power
motor gear on the power motor shaft, and remove the gear. Remove the four end cap
screws and lock washers, and remove the end
cap. Knock out the bearing and shim from
the end cap. Knock-out holes are provided
in the end cap for this purpose. Remove the
rotor assembly from the motor housing. The
bearing on the opposite end of the rotor shaft
will be removed with the rotor. Remove the
dust guard from the lower end of the rotor
shaft. Remove the bearing and dust guard
from the opposite end of rotor shaft. Be
careful not to lose the shims that are mounted behind the bearings in the end caps.
13G23. Assembly of the power motor. (See
Figure 13-41.) Place the shim in the front
end of the motor housing. Place the dust
washer and bearing on the upper end of the
rotor shaft, with the shoulder of the dust
washer facing the bearing. Insert the rotor
assembly into the motor housing. Install the
dust washer and bearing on the lower end of
the rotor shaft in the same manner as described above. Place the shim in the end
cap. Place the end cap over the lower end
166
Figure 13-40. Removing power motor.
of the rotor shaft, and in position on the motor housing. Secure the end cap with the
four screws and lock washers provided. Align
the power motor gear on the end of the rotor
shaft, and install the pin through the gear and
shaft. Tighten the setscrew that secures the
gear to the shaft.
13G24. Installing the power motor. (See
Figure 13-39.) Place the power motor in position on the mounting plate, using care when
meshing the gears. Secure the motor to the
mounting plate with the four screws provided.
Solder the electrical leads to the terminals on
the motor.
13G25. Removing the power motor drive gear
assembly. (See Figure 13-42.) Remove the
four screws and lock washers that secure the
gear assembly to the back end of the mounting
plate, and remove the gear assembly. There
may be shims mounted between the gear box
167
Figure 13-41. Power motor partially disassembled.
and mounting plate. Shims are to be installed
in the same position at assembly.
13G26. Disassembly of the power motor drive
gear assembly. (See Figure 13-43.) Remove
the nut and washer from the driven gear end
of the worm shaft. Drive out the tapered pin
and loosen the setscrew securing the driven
gear on the worm shaft; then remove the
gear. Remove the dust washer, bearing, and
shim from the driven gear end of the worm
shaft. Remove the nut and lock washer, dust
washer, and bearing from the lower end of the
worm shaft. Pull the worm shaft toward the
top of the gear box; then tilt the worm shaft
upward and remove it from the gear box. Remove the nut and lock washer from the driving gear end of the worm shaft. Knock out
the pin, and loosen the setscrew that secures
the driving gear on the worm gear shaft, and
remove the driving gear. Remove the dust
washer, and bearing from the driving gear
end of the worm shaft. Remove the nut and
lock washer from the worm gear end of the
shaft. Knock out the pin, and loosen the
setscrew that secures the worm gear to the
worm gear shaft. Drive the worm gear shaft
out of the worm gear. Knock out the bearing
outer races from the gear box.
Figure 13-42. Power motor drive gear assembly removed.
168
13G27. Assembly of the power motor drive
gear assembly. (See Figure 13-43.) Install a
bearing outer race in each of the two recesses
in the sides of the gear box. Hold the worm
gear in position within the gear box, with the
gear hub toward the convex side of the gear
box; then insert the worm gear shaft from
right to left through the bearing recesses in
the gear box, and through the worm gear hub.
The long end of the worm gear shaft is toward
the left side of the gear box. Align the hole
in the shaft and worm gear hub, and install
the tapered pin. Tighten the hub setscrew.
Install the shims, bearing, dust washer, lock
washer and nut on the worm gear end of the
worm gear shaft. Install the shims, bearing,
dust washer, and driving gear on the driving
gear end of the worm gear shaft. Align the
hole in the shaft and in the driving gear hub,
and install the tapered pin. Install the lock
washer and nut on the driving gear end of the
shaft. Install the bearing outer race in the
recess in the top of the gear box. Insert the
long end of the worm shaft through the lower
side of the upper section of the gear box.
Move the shaft upward until the lower end
of the shaft clears the lower section of the
gear box, then insert the lower end of this
shaft into the lower section of the gear box.
Place the shims, bearing, dust washer, and
Figure 13-43. Power motor drive gear assembly disassembled.
169
driven gear on the upper end of the worm
shaft. Align the hole in the shaft and in the
driving gear hub, and install the tapered pin.
Tighten the driven gear hub setscrew. Install
the lock washer and nut on the driven gear
end of the worm shaft. Install the shims,
bearing, dust washer, lock washer, and nut
on the lower end of the worm shaft. Turn
the gears and shafts by hand to be sure that
the parts operate freely.
13G28. Installing the power motor drive gear
assembly. (See Figure 13-42.) Align the
shims, if used previously, between the gear
box, and the main mounting plate, and secure
the gear box to the mounting plate with the
four screws and lock washers provided.
Figure 13-44. Condenser and resistor assembly
removed.
13G29. Removing the condenser. (See Figure 13-44.) Remove the unit from the case.
Unsolder and tag the leads at the condenser.
Remove the two screws, nuts, and lock washers that secure the condenser to the mounting
bracket, and remove the condenser. The other
condenser is removed in the same manner.
13G30. Installing the condenser. (See Figure 13-44.) Place the condenser in position
on the mounting bracket, and secure it with
the two screws, lock washers, and nuts provided. Solder the leads to the condenser.
Install the unit in the case.
13G31. Removing the 250-ohm resistor.
(See Figure 13-44.) Remove the unit from
case. Unsolder and tag the leads. Remove
one elastic stop nut and flat washer from
one end of the resistor shaft, and pull the resistor from the shaft.
13G32. Installing the 250-ohm resistor.
(See Figure 13-44.) lace the resistor in
position on the resistor shaft in the mounting
bracket, and install the flat washer and elastic
stop nut securing the resistor to the bracket.
Solder the leads to the resistor. Install the
unit in its case.
13G33. Replacing the 750-ohm resistor.
(See Figure 13-44.) Remove the unit from its
case. Unsolder and tag the leads. Remove
the elastic stop nut and fiber spacer from the
resistor stud, and remove the resistor. The
other 750-ohm resistor is removed in the same
manner. Place the resistor on the resistor
stud, and secure it with a fiber spacer and
elastic stop nut. Solder the lead to the terminal. Install the unit in its case.
13G34. Removing the condenser and resistor
assembly as a unit. (See Figure 13-44.) Remove the unit from the case. Unsolder and
tag the ten leads. Remove the three screws
that secure the condenser and resistor mounting bracket to the back of the main mounting
plate, and remove the condenser and resistor
assembly.
13G35. Installing the condenser and resistor
assembly as a unit. (See Figure 13-44.) Place
the condenser and resistor mounting bracket
in position on the mounting plate, and secure
with the three screws. Solder the leads to
the condensers and resistors.
13G36. Removing the follower assembly.
(See Figure 13-45.) Remove the cover from
the case. Remove the four screws and lock
washers that secure the follower assembly to
the main mounting plate, and carefully remove the follower assembly. The follower
frame is pinned to the mounting plate, and
must be removed carefully so as not to bend
the pins.
13G37. Disassembling the follower. (See
Figure 13-45.) Disassemble the follower as
170
1. UNIVERSAL CENTER
2. UNIVERSAL JOINT
3. FOLLOWER
4. FOLLOWER WASHER
5. PIN
6. BEARING CLAMP
7. LEAD SCREW
8. BEVEL GEAR
9. FOLLOWER HUB
10. FOLLOWER TENSION SPRING
11. FOLLOWER SLIDE ROD Figure 13-45. Follower assembly removed.
follows: Drive out the tapered pin from the
follower hub. Remove the nut and lock
washer from the right end of the universal
joint. Remove the three screws that secure
the bearing clamp to the right side of the
follower frame, and remove the bearing clamp.
Pull the universal joint out of the left side of
the follower frame. Lift the follower assembly out of the frame. The inner bearing
clamp is removed with the follower. Remove
the three screws that secure the follower
washer, follower, and follower hub together,
and remove the follower. Remove the follower bearings as follows: Remove the outer dust
washer, bearing, and inner dust washer from
the right side of the follower frame. Remove
the outer dust washer, bearing, inner dust
washer, and shim from the left side of the
frame.
13G38. Assembly of the follower. (See Figure 13-45.) Assemble the follower, follower
hub, and follower washer, and secure them
with the three screws provided. Place the
dust washer, and bearing on the universal
joint, and partially insert the universal joint
through the left side of the follower frame,
being sure to align the bearing in the frame
recess. Place the dust washer and shim adjacent to the ball bearing on the universal
joint. Hold the follower and inner bearing
clamp in position within the follower frame,
and insert the universal joint through the
follower and inner bearing clamp. Install the
inner dust washer, bearing, and outer dust
washer over the end of the universal joint and
into position in the recess in the right side
of the follower frame. Place the outer bearing clamp in position on the right side of
the follower frame. Align the holes in the inner and outer bearing clamps and install the
three screws that secure the clamps to the follower frame. Install the lock washer and
nut on the end of the universal joint. Align
the hole in the follower hub and hole in the
universal joint, and install the tapered pin.
13G39. Removing the follower lead screw.
(See Figure 13-46.) Remove the follower
assembly from the mounting plate. (See Section 13G36.) Remove the tapered pin, loosen
the setscrew that secures the bevel gear on the
lead screw, and remove the bevel gear. Remove the four bearing clamp retaining screws,
and the right bearing clamp. Remove the right
bearing and bearing outer race. Remove the
left bearing clamp, bearing, and outer race in
the same manner. Unscrew and remove the
follower lead screw from the follower slide
frame.
13G40. Installing the follower lead screw.
(See Figure 13-46.) Screw the follower lead
screw into the follower slide frame. Move the
follower slide frame clear of one bearing recess, and install the bearing outer race with
the race flange facing outward; install the
bearing and bearing clamp. Repeat this
operation on the opposite end of the lead
screw. Place the bevel gear on the right
end of the follower lead screw. Align the
hole in the gear with the hole in the lead
screw, and install the tapered pin. Tighten
the setscrew in the gear hub. Place the follower assembly in position on the main
mounting plate and secure it with the four
screws and lock washers provided.
8. UNIVERSAL CENTER
9. UNIVERSAL JOINT
10. FOLLOWER TENSION SPRING
11. FOLLOWER SLIDE ROD
12. COUNTER COMPONENT FRAME
13. SETSCREW
14. BEVEL GEAR
15. TAPERED PIN
Figure 13-46. Follower lend screw removed.
13G41. Removing the follower slide rod. (See
Figure 13-45.) Remove the follower assembly from the mounting plate. (See Section
13G36.) Remove the follower tension spring
by removing the nut, tension screw, spring,
and spring cap. Knock out the tapered pin
that secures the slide rod in the follower
slide frame, and pull out the slide rod.
13G42. Installing the follower slide rod. (See
Figure 13-45.) Place the slide rod in position
in the follower slide frame, and install the
tapered pin that secures the rod in the frame.
Install the spring cap, tension spring, tension
screw, and tension screw nut. Place the follower assembly on the mounting plate, and
secure it with the four screws and lock washers provided.
7. UNIVERSAL CENTER
8. FOLLOWER TENSION SPRING
9. ROTATING DISK
10. FOLLOWER
11. FOLLOWER LEAD SCREW BEVEL GEAR
12. COMPONENT FRAME UPPER BEVEL GEAR
Figure 13-47. Follower, differential, and rheostat assemblies installed.
172
13G43. Preparing the follower assembly for
adjustment. (See Figure 13-47.) Prepare
the follower assembly for adjustment after
disassembly in the following manner: Adjust
the follower tension spring so that there is
a slight tension between the follower and
the rotating disk. Unmesh the bevel gears
by supporting the gear shaft of the component
frame assembly and knocking out the tapered
pin from the component frame upper bevel
gear hub. Loosen the setscrew in the gear
hub, and drop this gear from mesh with the follower lead screw gear. Remove the pin
from the universal center so that the disk
will rotate independently of the differential
assembly.
13G44. Method of adjusting the follower to
the center of the rotating disk. (See Figure
13-47.) Disengage the bevel gear on the component frame assembly from the lead screw
bevel gear in the following manner: Manually
move the main balance arm until the setscrew
and tapered pin in the gear hub are accessible;
then slip a piece of paper under the contact
arm to maintain the position of the tapered
pin and setscrew. Loosen the setscrew and
drive out the tapered pin, and unmesh the
gears. Be sure to support the shaft when
driving out the tapered pin in order to prevent bending of the shaft. Move the lead
screw gear until the follower runs in one
direction; then turn the lead screw gear in
the opposite direction until the follower just
starts to run in the opposite direction. Manually move the lead screw first one way and
then the opposite way until the follower will
not rotate in either direction. This is an
indication that the follower is in the center
position of the rotating disk.
After positioning the follower in the
center of the disk, carefully mesh the two
beveled gears so that the lead screw gear is
not moved from its position. Install the
tapered pin and tighten the setscrew in the
component frame upper gear. Connect the
universal center by installing the pin in the
universal joint and universal center. Energize
the system, including at least one of the speed
and distance indicators. Manually move the
main balance arm to the right to raise the
speed pointer to exactly 5 knots. Place a piece
of paper between the contact arm and contacts
so that a speed indication of exactly .5 knots
is maintained. Measure the time required
for the distance counter to register exactly V,
mile on the speed and distance indicator. The
time should be 6 minutes, plus or minus
3 seconds. If the error is greater than 10
seconds, it is an indication that the slipping
clutch is not operating properly, or that the
follower is off center position considerably.
Test the slipping clutch for proper operation
as described in Section 13G45. Adjust the
follower to the center of the rotating disk
as described above.
13G45. Testing and adjusting the slipping
clutch. (See Figure 13-47.) Place a finger
on the distance transmitter driven gear and
slow down the transmitter. The rheostat
brush arm should rotate in a counterclockwise
direction. Removing the finger from the
transmitter driven gear should cause the rheostat brush arm to rotate to its original position. If the differential spider is turning and
the slipping clutch is slipping, indicated by
the rheostat brush arm not turning, tighten
the clutch spring adjuster in the following
manner: Loosen the setscrew in the clutch
spring adjuster and move the spring adjuster
to the left to tighten the adjustment on the
slipping clutch. Repeat the operation until
the rheostat brush arm turns with the differential spider.
13G46. Adjusting the rheostat spring tension.
(See Figure 13-47.) Another possible cause
of a slipping clutch is that the spring in the
rheostat is too tight. This causes the rheostat brush arm to stop turning when the differential spider is turning while the finger
is slowing down the action of the transmitter driven gear. Adjust the rheostat spring
tension as follows: Loosen the setscrew in the
damper hub while holding the rheostat brush
arm with the other hand. It is necessary to
hold the left end of the rheostat shaft, while
loosening the setscrew to prevent the spring
from ejecting parts from within the rheostat.
Carefully move the rheostat shaft assembly
slightly to the left to loosen the spring
173
tension, then tighten the setscrew in the damper
hub. Repeat this operation until the desired
rheostat spring tension is obtained.
13G47. Checking the spider operation. (See
Figure 13-47.) If the differential spider does
not turn when the transmitter driven gear is
slowed down, it is an indication that the follower tension spring is not adjusted properly.
Tighten the follower spring, and observe the
operation of the differential spider.
13G48. Checking the follower tension. (See
Figure 13-47.) After checking the slipping
clutch tension, and the rheostat spring adjustment, check the follower spring tension
as follows: Place a finger on the driven gear
of the distance transmitter, and stall the distance transmitter. If the follower tension is
correct, the follower will drive the differential spider, the spider will turn the rheostat
brush arm to its limit of travel, and the clutch
will slip,
13G49. Final checks of the follower, differential, and rheostat assemblies. (See Figure
13-47.) After checking the operation of the
follower, slipping clutch, and rheostat as
described above, check the timing on the distance counter of the speed and distance indicator as described in 13044. If the measured
time exceeds the tolerance of plus or minus
3 seconds, it is a positive indication that the
central position of the follower on the rotating disk is incorrect. Check the follower as
follows: Remove the note paper from the
contacts, and return the pointer to the zero
position. Unmesh the component frame upper gear as follows: Manually move the main
balance arm until the setscrew and tapered pin
are accessible; then slip the note paper under the contact arm to maintain the position
of the pin and setscrew. Be certain to support the shaft when driving out the taper pin
in order to prevent bending of the shaft.
Carefully turn the follower lead screw toward
the person facing the instrument, one bevel
gear tooth for each 3 seconds or less that the
measured time exceeds the 6 minutes for
1/2-mile. Turn the lead screw in the opposite
direction in the same manner for every 3
seconds or less below the measured 6 minutes
for the 1/2-mile indication. Carefully mesh
the bevel gears at the right of the follower
assembly, and tighten the setscrew in the
component frame upper gear. Do not install
the tapered pin at this time. Move the main
balance arm until the lead screws turn to make
the large end of the tapered pin hole accessible, then loosen the setscrew and install the
tapered pin through the gear hub and the
lead screw. Tighten the setscrew after the
tapered pin is installed. Make the distance
check described in Section 13G44. Then set
the speed pointer at 20 knots, and repeat the
time and distance check. The time elapsed.
should be 6 minutes plus or minus 3 seconds
for 2 miles distance indicated on the distance
counter.
13G50. Removing the rheostat. (See Figure 13-48.) The 500-ohm rheostat is replaced
as a unit. Remove the four screws and lock
washers that secure the rheostat bracket to
the main mounting plate, and lift the rheostat away from the mounting plate. Unsolder
and tag the electrical leads. Loosen the setscrew in the damper hub while holding the
rheostat shaft in position in the rheostat. It
is necessary to hold the shaft in position to
prevent the rheostat spring from ejecting
parts from the rheostat. Remove the damper
hub, spring, and frame assembly from the
rheostat shaft. Remove the nut and toothed
lock washer that secure the rheostat to the
bracket, and remove the rheostat.
13G51. Installing the rheostat. (See Figure
13-48.) Carefully remove the lock washer
from the shaft of the new rheostat while
holding the shaft in position within the rheostat. This is necessary to prevent the internal
parts from becoming lost when the washer is
removed. Remove the nut and toothed lock
washer from the replacement rheostat. Place
the rheostat in its bracket and secure it with
the toothed lock washer and nut provided.
Align the damper hub of the damper spring
and frame assembly with the flat-on end of
the rheostat shaft, and tighten the setscrew
in the damper hub. Place the rheostat and
bracket in position on the main mounting
plate, and secure them with the four screws
174
Figure 13-48. Rheostat removed.
provided. Be careful to align the damper
spring properly with the clutch plate. Solder
the electrical leads to the terminal on the
rheostat. Adjust the rheostat spring tension
as described in Section 13G46.
13G52. Removing the component frame assembly. (See Figure 13-49.) Remove the log
mechanism From its case. Place the mechanism on a bench, with the front of the log
facing upward. Drive out the two locating
pins as far as the main mounting plate so
that the frame assembly will clear the force
and balance arms. Remove the three screws
that secure the component frame assembly
to the mounting plate, and remove the frame
assembly.
13G53. Replacing the bearings. (See Figure 13-50.) Scribe a locating mark on the
component frame and the component slide so
that the slide and frame can be held in the
same relative position at assembly. Remove
the tapered pin and loosen the setscrew from
the component frame lead screw gear hub,
and remove the gear. Remove the upper bearing clamp retaining screws and bearing
clamp. Remove the shim, bearing, and bearing
inner race from the recess in the component frame. The lower bearing is removed
in the same manner. Install the bearing inner race in the recess in the component frame.
Install the bearing and shim; then install the
bearing clamp, and secure the clamp with
the two screws provided. Place the component lead screw gear in position on the
lead screw, align the hole in the gear hub
and in the screw, install the tapered pin and
tighten the setscrew in the hub. The bearing
on the opposite end of the component frame
is installed in the same manner.
13G54. Installing the component frame assembly. (See Figure 13-49.) Manually turn
the gear on the component frame assembly
until the scribe marks on the frame and slide
are aligned. Place the component frame
assembly in position on the front of the main
mounting plate, and secure it with the three
screws provided. Carefully drive in the locating pins from the back of the main mounting
plate.
13G55. Removing the cam and bracket assembly. (See Figure 13-51.) Remove the
case cover. Remove the pointer and dial. (See
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1. UPPER BEVEL GEAR
2. GEAR LOCK KNOB
3. B ADJUSTMENT KNOB
4. B SECTOR
5. SCRIBE MARKS
6. COMPONENT FRAME
7. LEAD SCREW
8. LOWER BEVEL GEAR
9. B ADJUSTMENT SCALE Figure 13-49. Component frame assembly removed.
Section 13G2.) Scribe a locating mark on the
speed transmitter drive gear of the cam and
bracket assembly, and the speed transmitter
driven gear on the speed transmitter so that
the gears may be meshed in the same relative
position at assembly. Remove the two screws
that secure the cam bracket assembly to the
mounting plate, and remove the cam and
bracket assembly.
13G56. Disassembly of the cam and bracket
assembly. (See Figure 13-52.) Remove the
handle screw from the pointer hub, and remove the pointer hub. Remove the three
screws and lock washers that secure the bearing clamp to the cam bracket, and remove the
bearing clamp. Knock out the tapered pin
and loosen the setscrew on the bearing collar. Pull the collar off the pointer shaft.
Remove the bearing from the recess in the cam
bracket. Remove the nut, lock washer, flat
washer, and bearing from the rear end of the
pointer shaft. Scribe a locating mark on the
cam and on the adjacent hub of the speed
transmitter drive gear so that the cam may
be installed in the same relative position at
assembly. Remove the setscrew between the
cam and helical gear, and remove the helical
gear and cam as a unit. Loosen the setscrew
in the speed transmitter drive gear hub, and
remove the drive gear from the pointer shaft.
Remove the three screws and lock washers,
176
Figure 13-51. Cam and bracket assembly removed.
and knock out the pin that secures the cam
to the cam hub, and remove the cam. Remove
the three screws that secure the gear to the
cam hub, and remove the gear.
13G57. Assembling the cam and bracket assembly. (See Figures 13-52 and 13-51.) Place
the cam on the cam hub, using the scribe
mark as a reference, and secure it with the
three screws and pin provided. Install the
helical gear on the cam hub, and secure it
with the three screws provided. Place the
speed transmitter drive gear on the pointer
shaft, and install the handle screw. Place the
bearing in the recess in the bracket, and install the bearing clamp. Place the pointer
shaft in the bracket, install the cam and hub
assembly on the pointer shaft, and install the
handle screw. Install the bearing collar on
the long end of the pointer shaft, and tighten
the setscrew in the nearing collar. Install the
pointer hub, and secure with the handle screw.
Place the bearing on the threaded end of the
pointer shaft, and install the flat washer, lock
washer, and nut.
Figure 13-52. Cam and bracket assembly disassembled.
177
13G58. Installing the cam and bracket assembly. (See Figure 13-51.) Place the cam
and bracket assembly in position on the main
mounting plate with the transmitter drive and
driven gears meshed according to the scribe
marks made on the gears when they were
removed. Install the two screws and dowel
pin that secure the cam and bracket assembly
to the main mounting plate. Install the dial
and pointer.
13G60. Disassembling the power motor
transmission shaft assembly. (See Figure 13-53.) Remove the bearing clamp, dust washer,
and bearing from the left bearing block. Remove the nut, lock washer, and flat washer
from the right end of the shaft. Remove the
tapered pin and loosen the setscrew that secures the shaft driving gear to the shaft, and
remove the gear. Remove the dust ring and
bearing from the right bearing block. Remove
Figure 13-53. Power motor transmission shaft assembly disassembled.
13G59. Removing the power motor transmission shaft assembly. (See Figure 13-53.) Remove the cam and bracket assembly. (See Section 13G55:) Remove the nut, lock washer,
and flat washer from the left end of the shaft.
Remove the left bearing block from the
mounting plate by removing the two block
retaining screws. Remove the two screws
from the right bearing block and pull the
right bearing block and the shaft assembly
to the right and away from the mounting
plate.
the bevel gear from the shaft by knocking out
the tapered pin and loosening the setscrew
in the gear hub. Knock out the two tapered
pins that secure the worm on the shaft, and
remove the worm.
13G61. Assembling the power motor transmission shaft assembly. (See Figure 13-53.)
Place the worm over the shaft, align the holes
in the worm and shaft, and install the two
tapered pins. Place the bevel gear on the right
end of the shaft, with the gear teeth toward
the worm, install the tapered pin and tighten
178
the setscrew in the gear hub. Place the bearing in the right bearing clamp. Insert the
end of the shaft into the bearing and install
the dust ring adjacent to the bearing. Place
the drive gear on the shaft, with the gear
hub facing the end of the shaft, and install the
tapered pin. Install the flat washer, lock
washer, and nut on the right end of the shaft.
Install the bearing in the left bearing block.
Install the dust washer and bearing clamp in
the left bearing block, and secure the clamp
with the two screws provided. Insert the
shaft assembly under the main balance arm and
force arm assemblies, from right to left, and
insert the end of the shaft into the left bearing block. Secure the bearing block to the
mounting plate with the two screws provided.
Align the right bearing block on the mounting plate and install the two screws that
secure the bearing block to the mounting
plate. Install the flat washer, lock washer,
and nut on the left end of the shaft. Install
the cam and bracket assembly. (See Section
13G58.)
13G62. Removing the main force arm. (See
Figure 13-54.) Remove the log mechanism
from the case. Remove the earn and bracket
assembly. (See Section 13G55.) Unscrew and
remove the spring thimble and adjusting
screw assembly from the top of the spring
barrel assembly of the A-adjustment mechanism. Insert the short screwdriver within
the spring barrel, unscrew the connector
screw that joins the A-mechanism with the
rocker of the auxiliary balance arm, and remove the A-adjustment mechanism. From
the back of the main mounting plate, remove
the nut and flat washer that secure the main
force arm shaft to the main mounting plate,
and remove the main force arm. The force
load spring is removed from the main force
arm shaft when the assembly is lifted away
from the mounting plate.
13G63. Disassembly of the main force arm.
(See Figure 13-55.) Remove the four screws
(two on each side) that secure the bearing
clamps to the top of the main force arm, and
lift off the bearing clamps and the A-adjustment mechanism from the main force arm.
Remove the nut, lock washer, dust washer,
Figure 13-54. Main force arm removed.
and bearing from one side of the A-adjustment axle. The bearing on the opposite side
of the axle is removed in the same manner.
Remove the nut, lock washer, and dust washer
from the front of the main force arm shaft,
and pull the shaft to the rear and out of the
main force arm. The rear dust washer is removed with the main force arm shaft. Remove the two bearings and bearing spacer
from the force arm.
13G64. Assembly of the main force arm.
(See Figure 13-55.) Place the rear bearing
in the recess in back of the main force arm.
Place the rear dust washer in position on the
rear of the main force arm shaft. Hold the
9. MAIN FORCE ARM.
10. BEARING SPACER.
11. COUNTERWEIGHT.
12. BEARING PIN.
13. CAM FOLLOWER.
14. MAIN FORCE ARM SHAFT.
15. FORCE LOAD SPRING.
Figure 13-55. Main force arm partially disassembled.
bearing spacer in position within the force
arm, and carefully insert the main force arm
shaft from the rear of the arm, through the
rear bearing and spacer to the front end of
the arm. Install the front bearing, dust washer, lock washer, and nut on the front end of
the main force arm shaft. Install the bearing,
dust washer, lock washer, and nut on one
side of the A-adjustment axle. The bearing
on the opposite side of the axle is installed
in the same manner. Place the A-adjustment
mechanism in position on top of the main
force arm, install the two bearing clamps,
and secure each clamp with the two screws
and lock washers provided.
13G65. Installing the main force arm. (See
Figure 13-54.) Place the force load spring
on the rear end of the main force arm shaft,
with the offset in the spring engaged in the
slot of the main force arm. Carefully place
the main force arm in position on the main
mounting plate, with the main force arm shaft
inserted through the opening provided in the
mounting plate and with the spring end also
engaged in the hole provided in the mounting
plate. Install the flat washer and nut that
secure the main force arm shaft to the main
mounting plate. Install the connector screw
of the A-adjustment assembly into the rocker
in the top of the auxiliary balance arm. Install the spring thimble and adjusting screw
into the spring barrel of the A-adjustment
mechanism. Calibrate the instrument. (See
Chapter 15.)
13G66. Removing the auxiliary and main
balance arms. (See Figure 13-56.) Cut the
string that secures the electrical lead to the
main balance arm. Remove the three screws
and lock washers that secure the auxiliary and
main balance arm assembly to the main mounting plate. Lift the assembly upward, and
turn it sideways to make the electrical lead
to the contact arm accessible. Unsolder the
electrical connection from the terminal on the
contact arm, and remove the auxiliary and
main balance arm assembly.
13G67. Disassembly of the auxiliary and
main balance arm assembly. (See Figure 1357.) Remove the lock nut and thin nut from
top of the B-spring, and disengage the spring
1. INDEX SCREW
2. B SPRING
3. GUIDE BEARINGS
4. CONNECTOR SCREW
5. THRUST PLATE
6. FRONT SECTION AUXILIARY BALANCE ARM
7. MAIN BALANCE ARM
8. CONTACT ARM
9. AUXILIARY BALANCE ARM CENTER SUPPORT
10. MAIN FORCE BEARING, ASSEMBLY
11. MAIN BALANCE ARM ADJUSTING SCREWS
12. COUNTERWEIGHT
13. BEARING CLAMP Figure 13-56. Auxiliary and main balance arm
assembly removed.
181
1. LOCK NUT
2. THIN NUT
3. B SPRING
4. CONNECTOR SCREW
5. SPRING FORCE HUB
6. NUT
7. DUST WASHER
8. BEARING
9. BEARING SHAFT
10. DOUBLE DUST WASHER
11. AUXILIARY ARM EXTENSION
12. LOCK WASHER
13. FLAT WASHER
14. FILLISTER-HEAD SCREW
15. FRONT SECTION OF AUXILIARY BALANCE ARM
16. SHIM
17. CONTACT ARM ASSEMBLY
18. THRUST PLATE
19. ROCKER BEARING
20. FLATHEAD MACHINE SCREW
21. MAIN BALANCE ARM
22. COUNTERWEIGHT
23. MAIN FORCE BEARING ASSEMBLY
24. BEARING CLAMP
25. SPACER
26. MAIN BALANCE SHAFT
27. ROCKER
28. REAR SECTION OF AUXILIARY BALANCE ARM
Figure 13-57. Auxiliary and main balance arm partially disassembled.
182
from the auxiliary balance arm. Unscrew and
remove the B-spring connector screw from
the rocker. Remove the two screws (one on
each side) that secure the thrust plates to the
rocker bearings and remove the thrust plates.
Remove the two screws that secure the rocker
bearings in the main balance arm, and remove
the bearings and rocker from the top of the
main balance arm. The other rocker and the
bearings at the top of the main balance arm
are removed in the same manner. Remove the
two bearing clamp retaining screws and bearing clamp from the front of the main force
bearing assembly. Remove the hexagonal nut
from the front of the main balance shaft;
then pull the main balance shaft to the
rear and out of the: auxiliary and main balance
arms. Remove the bearing, shim, and spacer
from the front end of the balance shaft
as the shaft is pulled to the rear. Lift the
main force bearing assembly (bracket) away
from the arm assembly. Remove the dust
washer, spacer, second dust washer, shim,
and bearing from the recess in back of the
main force bearing. Remove the screw that
secures the two sections of the auxiliary
balance arm at the center support. Remove
the two screws that secure the two sections
of the auxiliary balance arm at the top of
the arm. Remove the nut, lock washer, and
dust washer from each end of the spring force
hub. Carefully pull the two sections of the
arm apart.
The two sections of the auxiliary balance
arm are pinned together, and the sections must
be pulled straight away to prevent bending
the pins.
Remove the bearings and spring force
hub. Remove the nut and lock washer that
secure the guide bearing assembly to the end
of the auxiliary balance arm, and remove the
bearing assembly. Remove the dust washer,
bearing and double, dust washer from the
bearing shaft. Remove the nut, rear dust
washer, and second bearing from the other
end of the bearing shaft. Remove the screw
that secures the contact arm assembly to the
main balance arm, and remove the contact
assembly.
13G68. Assembly of the auxiliary and main
balance arm assembly. (See Figure 13-57.)
Mount the rocker assembly at the top of the
main balance arm in the following manner:
Install one rocker bearing in one side of the
recess at top of the main balance arm. Place
the rocker in approximate position in the installed rocker bearing. Place the second
rocker bearing in approximate position on the
opposite side of the main balance arm. Secure
the rocker bearings to the main balance arm
with the two screws provided (one on each
bearing). Place the thrust plates in position
on the outer sides of the rocker bearings (one
on each bearing) and secure, with one screw
for each thrust plate. The other rocker assembly is installed in the same manner.
Align the B-spring with the rocker, and
tighten the connector screw in the rocker.
Place both sections of the auxiliary balance
arm in approximate position on each side of
the main balance arm, and place the spring
force hub between the upper sections of the
auxiliary balance arm, with the long section.
of the force hub upward. Align the pin holes
and pins of the two sections of the auxiliary
balance arm, and squeeze the two sections together into position on the main balance arm.
Secure the auxiliary balance arm at its center
support with one screw, and at the top of the
arm with two screws. Install the bearing, dust
washer, lock washer, and nut on each end of
the spring force hub. Install a bearing in each
of the two sections at the bottom of the auxiliary balance arm. Place the main force bearing assembly (bracket) in position at the
bottom of the auxiliary and main balance
arms.
Assemble the bearing, dust washer,
spacer, second dust washer, and shim, in that
order, on the back of the balance shaft. Align
all parts and carefully insert the balance shaft
from the rear of the main force bearing
through the auxiliary and main balance arms
far enough to install the shim and outer dust
washer on the front end of the balance shaft.
Completely insert the balance shaft through
the auxiliary and main balance arm assemblies. Install the spacer, shim, and bearing on
the front end of the balance shaft. Install the
hexagonal nut on the front end of the shaft.
Install the bearing clamp on the forward side
183
of the main force bearing (bracket), and
secure the bearing clamp with the two screws
provided. Install the guide bearings as follows : Assemble the dust washer, and bearing
on the short threaded end of the bearing pin.
Assemble the double dust washer, second
bearing, and dust washer from the other end
of the bearing pin. Install the bearing pin,
with its assembled bearings, through an opening in the arm extension at the top of the
auxiliary balance arm, and secure it with a nut
on the front end of the bearing pin. Place the
B-spring assembly into the spring force hub,
and install the thin nut and lock nut on top
of the B-adjustment assembly. Install the
contact arm assembly in position on the main
balance arm, and secure it with one screw.
13G69. Installing the auxiliary and main balance arms. (See Figure 13-56.) Place the
auxiliary and main balance arm assemblies in
approximate position on the mounting plate.
Solder the electrical lead to the terminal on
the contact arm assembly. Install the three
screws and lock washers that secure the auxiliary and main balance arm assemblies to the
main mounting plate. Align the electrical
lead along the main balance arm and secure
it in position with string. Install the main
force arm (see Section 13G65). Install the
cam and bracket assembly (see Section 13G58).
Calibrate the instrument as described in
Chapter 15.
13G70. Replacing the contact arm. (See
Figure 13-58.) The contact arm and contact
are replaced as a unit. Remove the cover from
the master transmitter indicator case. Unsolder the electrical lead from the contact arm
Figure 13-58. Contact arm assembly removed.
terminal. Remove the screw that secures the
contact arm to the main balance arm, and
remove the contact arm assembly. Unhook the
contact spring from the contact arm. Remove
the pigtail from the contact arm. Loosen the
setscrews that secure the pivots in the contact
arm bracket, loosen the pivots, and remove.
the contact arm and shaft as a unit. Place the
new contact arm in position, and tighten the
pivots. Tighten the setscrews. Install the pigtail on the contact arm. Engage the contact
spring on the end of the contact arm. Place
the contact arm assembly in position on the
main balance arm, and install the arm retaining screw. Solder the electrical lead to the
terminal on the contact arm bracket.