Challenger 35, Challenger 45 and Challenger 55 Agricultural Tractors Implement, Steering and Brake Hydraulic Systems Caterpillar

Purge the Air from the Service Brakes

Illustration 1	g00509114
(1) Rubber stopper (2) Transparent tubes (3) Oil filler tube

1. Install rubber stopper (1) into the end of oil filler tube (3) .

   1. Oil filler tube (3) is located to the right of the implement valve bank.

2. Attach two transparent hoses (2) to the purge valve on each side of the center housing.

3. Insert the other ends of hoses (2) through stopper (1) .

4. Open each purge valve by one-half turn.

5. Start the engine. Run the engine at low idle.

6. Warm the oil to 60°C (140°F). At least two segments should be visible on the bargraph for hydraulic oil temperature.

7. Depress the brake pedal by approximately 100 to 125 mm (4 to 5 inch).

8. Hold the brake down for one minute or hold the brake until the oil that is flowing through tubes (2) is free of air bubbles.

9. If the oil still has air bubbles, pump the brake pedal until the oil that is flowing through tubes (2) is free of air bubbles.

10. Close both purge valves while the brake pedal is depressed.

11. Stop the engine.

Purge a Contaminated System

Illustration 2	g00509115
(4) Center housing (5) Plug

1. Remove one plug (5) from the bottom of each piston cavity of center housing (4) .

   Note: Make sure that the oil from each port is contained.

2. Start the engine. Run the engine at low idle.

3. Depress the brake pedal by approximately 100 to 125 mm (4 to 5 inch).

4. Hold the brake in this position for several minutes.

5. Release the brake pedal and stop the engine.

6. Install plugs (4) .

7. Check the hydraulic oil level. Fill the sump, if necessary.

8. Purge the air from the service brakes. Refer to "Purge the Air from the Service Brakes".