4-13. TROUBLESHOOTING (CONT)
TEST OR INSPECTION
HYDRAULIC SYSTEM - CONT
Steering and suspension system hydraulic lines are under pressure even when
APU is not running. Do not attempt to tighten, loosen, adjust, or repair fittings,
lines, or hoses until semitrailer is supported by support legs (para. 2-22 and 2-23)
and all pressure is relieved or injury to personnel may result.
Hydraulic fitting/joint leaks.
a. Check tightness of fittings and tighten. If tight and leaking, continue with next corrective action.
While performing hydraulic maintenance, it is important to accurately tag both
ends of a hose or tube and associated fittings. When removing or installing any
hydraulic hoses or tubes, use two wrenches, one to hold the fitting, and one to
turn the hose or tube or damage to equipment may result.
b. Disassemble and inspect for fittings metal-to-metal seal problems, defects in surface texture of
flares, and pitting or breaks. Reassemble joints using pipe sealant (item 18, appx. E) as required
for pipe threaded fittings. If joint still leaks, replace parts as necessary.
Check hydraulic system for split or ruptured hydraulic hoses and tubes.
a. Replace all defective tubes.
b. If a hose needs to be repaired or replaced, remove defective hose and notify DS maintenance.