PREVENTIVE MAINTENANCE
SECTION V
Figure 5B-3. Swing Brake Adjustment
The boom hoist and third drum clutches are hydraulically
applied, spring released. These clutches are similar, but are
arranged for rotation in opposite directions.
The swing clutches are also hydraulically applied and
spring released. These clutches are identical but are ar-
ranged for rotation in opposite directions, and therefore are
not interchangeable.
No adjustment should be necessary during the life of the
Figure 5B-2. Boom Hoist Planetary Brake
above clutch bands. The pistons of the clutch cylinders will
Adjustment (100P632)
compensate for lining wear by increasing the piston stroke
as the lining wears. Therefore, the extent of lining wear and
the available piston stroke are the only factors limiting the
the dead end of the band. See the Shop Manual for relining
capabilities of these clutches.
instructions.
NOTE
CHECK SWING BRAKE
Since lining wear will usually be greatest at the dead
The swing brake is a spring set-hydraulically released type
end of the clutch band, the clutch band may be turned
brake.
around when wear has reduced the thickness of the
To adjust the swing brake, proceed as follows (see Figure
lining at the dead end to within 1/8 inch of the rivets.
When wear has reduced the thickness of the lining to
within 1/16 inch of the rivets the band should be re-
1. With the brake set (hydraulic pressure released) loosen
Iined. Refer to the appropriate area in the Shop
jam nuts (01) and turn adjusting nuts (02) so that the length
Manual for specific settings and procedures.
of springs (03) is 4-1/4 inches.
2. Loosen jam nut (04) and adjust nut (05) so that the pis-
CHECK LEFT AND RIGHT DRUM PAWLS
ton of cylinder (06) has one inch stroke when the brake is re-
The left and rlght drum pawls are hydraulically engaged and
leased.
spring released. To check and adjust the pawls, proceed a
follows (see Figure 5B-4):
CHECK CLUTCHES
The left and right drum clutches are hydraulically applied,
1. With the machine running, move the left and right drum
spring released. These clutches are identlcal, with the
pawl switches to the ON position to engage the pawls into
exception that they are arranged for rotation in opposite
the drum teeth.
directions. and therefore are not interchangeable. These
2. Check both pawls for complete engagement to the drum
clutches can be adjusted using shims See Shop Manual.
teeth.
Subsection 7D.
5-8
