TABLE 3-1. DIRECT AND GENERAL SUPPORT TROUBLESHOOTING (CONTD)
Test or Inspection
HOIST WILL NOT RAISE LOAD
Step 1. Defective hoist motor control valve.
Remove and inspect valve. (Refer to page 15-60.) If OK, do Step 2.
Step 2. Damaged primary drive assembly.
Repair or replace primary drive assembly. (Refer to page 15-36.)
Step 3. Damaged overrunning clutch.
Remove brake housing and associated lines from the primary housing. The clutch assembly is keyed and
bolted to the brake pinion. The clutch assembly should turn freely in the counterclockwise direction. Repair
Step 4. Sheared shaft on pump or damaged pump.
Install a 0 to 5000 psi (0 to 34,475 kPa/344.8 bar) 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
HOIST WILL NOT LOWER
Step 1. Damaged primary drive assembly.
Repair or replace primary drive assembly. (Re fer to page 15-36.)