Test For The Pressure Override Relief Valve (POR Valve)
(2) Pressure test ports. (3) POR valve.
Connect two pressure gauges to pressure test ports (2).
Release the parking brake. Move the parking brake
switch to the OFF position. This position will allow the
pumps to upstroke.
Set the speed range switch to the HIGH SPEED
Move the propel control lever in the FORWARD
position. Record the pressure at test port (2). The
pressure should be 45000 ± 1400 kPa (6525 ± 200 psi).
If the pressure at the POR valve is not correct, adjust
POR valve (3). Use a 13 mm wrench in order to loosen
the locknut Use a 4 mm Alien wrench in order to adjust
the relief pressure of the POR valve. Turn the adjusting
screw clockwise in order to increase the pressure. Turn
the adjusting screw counterclockwise in order to
decrease the pressure.
Remove plugs and reconnect brake line (1) to the front
and rear propel motors.
Piston Motor Case Leakage (Drum Propel) - Test
SMCS Code: 4351-081-FW
Hose (36 inches)
Personal injury or death can result from sudden machine
Sudden movement of the machine can cause injury to
persons on or near the machine.
To prevent injury or death, make sure that the area around
the machine is clear of personnel and obstructions before
operating the machine.
Care must be taken to ensure that fluids are contained
during performance of inspection, maintenance, testing,
adjusting and repair of the product. Be prepared to collect
the fluid with suitable containers before opening any
compartment or disassembling any component containing
Refer to Special Publication, NENG2500, "Caterpillar Tools
and Shop Products Guide" for tools and supplies suitable
to collect and contain fluids on Caterpillar products.
Dispose of all fluids according to local regulations and
Before you conduct the testing and adjusting, refer to the
Stop the machine. Apply the parking brake.
Place the propel control lever in NEUTRAL position.