HYDRAULIC SYSTEM TESTS - CONTINUED
PRESSURE RELIEF VALVE TESTS - CONTINUED
Main Relief Valve.
Do NOT remove hydraulic tank filler cap or disconnect or remove any hydraulic system line
or fitting unless hydraulic system pressure has been relieved. Hydraulic system pressure can
be over 2500 psi (17,237 kPa), even with engine and pump OFF. To relieve pressure, lower all
hydraulic attachments to the ground and shut down engine. Move control levers through all
operating positions, then SLOWLY loosen hydraulic tank filler cap. After maintenance,
tighten all connections before applying pressure. Escaping hydraulic fluid under pressure can
penetrate the skin, causing serious injury or death.
At operating temperature hydraulic oil is hot. Allow hydraulic oil to cool before disconnecting
any hydraulics. Failure to do so could result in injury.
Operate machine until hydraulic system is at operating temperature. Lower implements to the ground, so that bull-
dozer blade is level. Shut down engine. Move all hydraulic control levers to all positions to relieve pressure in
lines. Return all control levers to HOLD position.
Install a 0-4000 psi (0-2,7579 kPa2) gage in pressure tap (3) located in output line from large section (4) of