TM 5-3810-307-24-1-1
Direct/General Support Troubleshooting - Continued
SYMPTOM
PROBABLE CAUSE
CORRECTIVE ACTION
1. Hoist will not raise load
c. Damaged primary drive
c. Repair or replace primary drive
(continued).
assembly.
assembly.
d. Damaged overrunning
d. Remove brake housing and
clutch.
associated lines from primary
housing. The clutch assembly
is keyed and bolted to the
center drive shaft of the drum.
The clutch assembly should
turn freely in the counter-
clockwise direction. Repair or
replace as necessary.
e. Sheared shaft on pump or
e. Install a 0 to 5000 psi (0 to
damaged pump.
34,475 kPa) gauge in the inlet
line of the hoist valve bank.
Activate the system. No
pressure or excessively low
pressure indicates a damaged
pump or drive shaft. Repair or
replace as necessary.
f. Motor control valve out of
f. Contact Grove Worldwide,
adjustment.
Product Support for valve
adjustment.
2. Hoist will not lower.
a. Damaged relief valve.
a. Repair or replace valve.
b. Damaged hoist control
b. Repair or replace valve.
valve.
c. Repair or replace primary drive
c. Damaged primary drive
assembly.
assembly.
d. Contact Grove Worldwide,
d. Motor control valve out of
Product Support for valve
adjustment.
adjustment.
3. Hoist down operation
a. Damaged circuit relief valve.
a. Repair or replace valve.
slow.
b. Damaged hydraulic pump.
b. Damaged hydraulic pumps
normally build heat. By hand,
carefully check the temperature
of pump in relation to other
hydraulic pumps. Repair or
replace pump as necessary.
4. Hoist up operation slow.
a. Damaged circuit relief valve.
a. Repair or replace valve.
1-5-27
