18
TROUBLE “D” CONTINUED FROM
PREVIOUS PAGE
The hoist will not raise the rated
load.
3. Be certain hydraulic system tem-
perature is not more than 180°F
(82°C). Excessive hydraulic oil
temperatures increase motor in-
ternal leakage and reduce motor
performance.
4. Hoist line pull rating is based on
first layer of wire rope.
5. Rigging and sheaves not operating
efficiently.
B. Apply a stall pull load on the hoist
while monitoring pressure.
C. Compare gauge reading to hoist
specifications. Adjust relief valve
as required.
NOTE:
If pressure does not increase
in proportion to adjustment, relief
valve may be contaminated or worn
out. In either case, the relief valve
may require disassembly or replace-
ment.
Same as remedies for Trouble D1
and D2.
Same as remedies for Trouble E2.
Refer to hoist performance charts for
additional information.
Perform rigging service as recom-
mended by crane manufacturer.
E
1. Same as D1.
2. Be certain that the hydraulic sys-
tem temperature is not more than
180°F. Excessive hydraulic oil
temperatures may be caused by:
A. Plugged heat exchanger.
B. Too low or too high oil level in hy-
draulic reservoir.
C. Same as D2.
D. Hydraulic pump not operating ef-
ficiently.
3. Excessively worn or damaged in-
ternal hoist parts.
Same as remedies for Trouble D1.
Thoroughly clean exterior and flush
interior.
Fill/drain to proper level.
Same as remedies for Trouble D2.
Prime mover low on horsepower or
RPM Tune/adjust prime mover.
Check suction line for damage.
If pump is belt driven, belts are slip-
ping. Replace/tighten belts.
Pump worn. Replace pump.
Disassemble hoist to inspect/replace
worn parts.
TROUBLE
PROBABLE CAUSE
REMEDY
