TM 5-5420-234-14&P
5-2. DIRECT SUPPORT TROUBLESHOOTING (continued).
2.
HOOK ARM DOES NOT LOAD (continued).
HOOK ARM LOAD PRESSURE TEST
WARNING
The LHS hydraulic system operates at oil
pressures up to 3,625 psi (24,994 kPa).
Never disconnect any hydraulic line or
fitting without first dropping pressure to
zero. Failure to comply with this warning
may result in serious injury or death to
personnel.
(1) Remove hose no. 2882 from fitting at rear of
main frame.
(2) Install tee fitting, hose adapter, hose, and
pressure gage between fitting and hose.
(3) Start engine and engage the PTO.
(4) Turn the light control switch to the STOP
LIGHT position. Place LHS MODE SELECT
switch in the HOOK ARM ONLY (manual
mode) position.
(5) Attempt to load the hook arm using the re-
TEE
mote control or cab controls.
FITTING
CAUTION
FITTING
HOSE
ADAPTER
Fully extending or retracting hydraulic
cylinders will put the hydraulic system
HOSE
into relief. This should be limited to 10
seconds. Failure to comply with this cau-
tion may result in damage to equipment.
NOTE
During an empty load cycle, the hydraulic
~
pressure will read approximately 1,000 psi
until the hook arm hydraulic cylinders are
fully extended. Full relief pressure of 3,100
to 3,300 psi will be reached at full extension
of the hydraulic cylinder.
HOSE
NO. 2882
(6) Observe the readings on the pressure gage
during loading.
PRESSURE
GAGE
(7) Shut off engine and turn off light control
switch.
(8) Remove tee fitting, hose adapter, hose, and
pressure gage from between fitting and hose
no. 2882.
(9) Install hose no. 2882 on fitting at rear of main
frame.
5-13
