Brake Efficiency Check
Do the Main Relief Valve Pressure Test before
doing the brake efficiency check.
Parking Brake Valve
(1) Brake wire connector.
Disconnect wire connector (1). This will allow the
parking brake to stay applied during the test.
Test Ports (2)
Test port for axle pump (forward direction). (3) Test port for drum
pump (forward direction).
Connect a 60 000 kPa (8700 psi) pressure gauge from
the 4C4892 ORFS Fittings Group to test ports (2) and
Start and run the engine at high idle until the hydraulic
oil temperature reaches 38°C (100F). Engine rpm
should be 2350 ± 50 rpm.
Release the parking brake. Slowly move the propel
control lever fully forward until the pressure gauge
readings exceed 25 000 kPa (3600 psi) or the drum
begins to turn.
The rear wheels must not spin during this test. If
wheel spin is a problem, move to a location with
better soil density.
As soon as the drum starts to turn, note the pressure
gauge readings. The pressure must not be less than
25 000 kPa (3600 psi).
If the pressure is less than 25 000 kPa (3600 psi), it is
an indication that the brake discs are worn and need to
Connect the wire connector for the brake.