TM 5-3810-306-34
TABLE 3-1. DIRECT AND GENERAL SUPPORT TROUBLESHOOTING (CONTD)
Malfunction
Test or Inspection
Corrective Action
70.
BOOM WILL NOT SWING IN EITHER DIRECTION
Step 1. Defective swing motor.
a.
Repair or replace swing motor. (Refer to page 15-133.)
Step 2. Swing brake not releasing properly.
a.
Repair as necessary. (Refer to page 15-126.)
Step 3. Defective swing box.
a.
Remove swing box and repair. (Refer to page 15-116.)
Step 4. Defective two-section hydraulic pump.
a.
Repair or replace pump. (Refer to page 13-26.)
71.
SWING OPERATION SLOW IN EITHER DIRECTION
Step 1. Worn or damaged output shaft bearings.
a.
Remove and disassemble swing box. (Refer to page 15-116.) Inspect bearings. If OK, do Step 2.
b.
Replace bearings.
Step 2. Defective swing motor.
a.
Remove and repair swing motor. (Refer to page 15- 133.)
Step 3. Defective two-section hydraulic pump.
a.
Repair or replace hydraulic pump. (Refer to page 13-26.)
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