Potentiometer Check; Assembly - Komatsu 930E-2 Shop Manual

Disassembly and Adjustment
1. Remove the capscrews (6, Figure 3-30) and lock-
washers (7) from lever assembly.
2. Remove potentiometer (8).
3. Bend tangs on washer (10) away from slots in
locknut (9).
a. If the lever assembly is to be completely disas-
sembled, loosen and remove locknut (9), along
with tang washer (10), spring (11), and washer
(12). Remove handle and shaft assembly (14).
Wash parts in clean solvent and inspect for
excessive wear, burrs, or scratches.
Replace defective parts.
b. If the lever assembly only requires adjustment,
loosen or tighten locknut (9) as follows:
The lever assembly should be adjusted such
that the frictional forces will hold the lever firmly
in the position selected by the operator. At the
same time, the adjustment should not be so
tight as to cause the operator to use undue
force to move the lever.
The position of the lever should remain station-
ary without moving down (applying the re-
tarder) from its own weight or due to machine
vibrations during truck operation.
When the desired adjustment is obtained, bend
tang on washer (10) into slot on locknut (9).

Potentiometer Check

The potentiometer (8, Figure 3-30) is spring-loaded to
the "OFF" position. With the switch assembly removed
from the lever assembly, make the following checks:
1. Rotate the "pot" clockwise to full "ON" and re-
lease. Be sure that the spring returns the "pot" to
the "OFF" position.
2. Using a reliable volt-ohm meter, 0 ohms should
be read in the "OFF" position.
3. Rotate the "pot" clockwise to full "ON" and hold.
2500 ±500 ohms should be recorded.
Replace the potentiometer if it does not meet
these specifications.
J03019 1/99

Assembly

1. If handle (16, Figure 3-30) or lever (15) has been
removed from shaft (14), assemble as follows:
a. Apply Loctite™ #271 to lever (15) and install
b. Apply Loctite™ #271 to opposite end of lever
2. Inspect the shaft bore and interior friction faces of
bracket (13) and remove any scratches or burrs,
or replace bracket.
Lightly lubricate the surfaces with a Multi-Purpose
EP NLGI Consistency #2 grease.
3. Insert the lever, handle, and shaft assembly into
bracket (13), and install washer (12), new spring
(11) [with the outer spring diameter against
washer (12)], tang washer (10), and locknut (9)
onto shaft (14).
4. Tighten and secure locknut (9) as described in
step 3.b. "Disassembly and Adjustment".
5. Move lever to the "UP" position as far as travel
permits. Align slot in potentiometer (8) with key
on shaft (14) and rotate pot until capscrew holes
line up with bracket.
Install washers (7) and capscrews (6) to secure
pot to bracket.
Tighten the socket head capscrews to 36 in. lbs.
(4.1 N.m) torque.
6. Install lever assembly to steering column.
Brake Circuit Component Service
lever fully into shaft (14).
(15) and install handle (16) onto lever.
Hand Tighten Only!
J3-31