FOAM 5178805 - Caterpillar

Brake Efficiency Check
Refer to the on the first page of Troubleshooting.
Do the Main Relief Valve Pressure Test before doing the brake efficiency check.
Parking Brake Valve
(1) Wire connector.1. Disconnect wire connector (1). This allows the parking brake to stay applied during the test.2. Position the speed selection switch to LOW speed.
Pressure Tap
(2) Forward propel pressure tap.3. Connect a 60 000 kPa (8700 psi) pressure gauge from the 4C4892 ORFS Fittings Group to propel pressure tap (2).4. Start and run the engine at high idle until the hydraulic oil temperature reaches 57°C (150°F). Engine rpm should be 2350 50 rpm.5. Place the machine in low range. Release the parking brake. Slowly move the propel control lever fully forward.6. With the propel lever full forward, observe the pressure at test port (2). The axle brakes should be capable of withstanding 41 340 kPa (6000 psi) without moving.7. If the pressure is less than 41 340 kPa (6000 psi), it is an indication that the brake discs are worn and need to be replaced.Propel Motor Case Drain Test
1. Stop the machine and apply the parking brake.
Propel Motor
(1) Hose assembly. (2) Propel motor.2. Disconnect hose assembly (1) from propel motor (2).
Right Side Engine Compartment
(3) Fabricated hose. (4) Flow meter.3. Install fabricated hose (3) to motor (2), and flow meter (4) to hose assembly (1).4. Install 4C-6500 temperature probe into the hydraulic tank. Operate the machine until the oil temperature reaches 57°C (150°F).5. Disconnect the electrical lead for the brake release solenoid. This allows the machine propel system to propel against the parking brake when the brake release button is applied. Place the machine in high range.6. Install two 51 675 kPa (7500 psi) gauges, one on the forward gauge and one on the reverse gauge, for the propel pump.7. With the parking brake applied and the machine propel lever in neutral, read the amount of oil flowing through flow meter (4). The flow should be less than 1.0 gpm.8. Activate the parking brake release button and slowly move the propel handle forward until 11 024 kPa (1500 psi) is noted on the gauge.9. Have an assistant read the amount of flow at flow meter (4). Hydraulic oil flow should be 2 .5 gpm greater than the value read in Step 7. The maximum flow allowable is 3.5 gpm.10. Repeat Step 9 four times rotating the axle 90° after each reading. It is necessary to reconnect the electrical lead (#777 purple wire for the brake release solenoid).11. Repeat Steps 8, 9 and 10 in reverse.12. If there is more than 3.5 gpm, the propel motor and/or flushing valve has too much leakage and should be repaired or replaced.13. Remove all test tooling and connect the hose assembly back to the propel motor.No-Spin Differential Operation Test
1. With the engine not running, raise the axle until all wheels are not contacting the ground surface. Place blocking stands under the axle to block the wheels off the surface. The CS-531 has parking brakes on the