631K OEM Wheel Tractor Machine Systems Caterpillar

Specifications

Introduction

Prepare the machine for testing by completing the procedure that is specified in the Service Manual module Troubleshooting, "Machine Preparation for Troubleshooting" for the machine that is being serviced.

Move the machine to a smooth, horizontal location. Move the machine away from other operating machines and away from personnel. Place the transmission direction control lever in the NEUTRAL position. Engage the parking brake. Lower the bowl to the ground. Stop the engine and place chocks in front of the wheels and behind the wheels.

Speed Tests

Perform all tests with the hydraulic oil at the normal operating temperature. Also, make the tests when the tractor engine is at high idle rpm. Use a stop watch to find the travel time.

If the travel time is not correct, check the following list:

• Check pump efficiency.

• Check the setting of the main relief valve.

• Check the operation of the valve spools in the control valve.

• Check the piston seals in the cylinders.

Travel Time for the Cushion Hitch Cylinder

Raise Time

1. Start the engine and run the engine at high idle.

2. Place the cushion hitch switch in the RIDE position.

3. The cushion hitch shall jump off the stop and raise to approximately 190 mm (7.5 inch) of the cylinder stroke in less than one second. The cylinder will then lower to the carry position.

   Note: Wait a minimum of 2 minutes between each check.

Lower Time

1. Start the engine and run the engine at high idle.

2. Place the cushion hitch switch in the LOCK DOWN position. The cushion hitch shall lower to the stop in less than 9 seconds.

Dead Engine

1. Start the engine and run the engine at high idle.

2. Place the cushion hitch in the RIDE position.

3. Turn the engine OFF.

4. The cushion hitch shall lower to the stop in 15 seconds. The accumulator oil shall also purge down in 15 seconds or less.

Steering Cycle Time

1. Start the engine and operate at LOW IDLE.

2. Release the parking brake and raise the bowl.

3. Slowly steer the machine to the right into the steering stop.

4. Increase engine speed to HIGH IDLE.

5. Steer the machine from the right steering stop to the left steering stop as fast as possible. The speed of the steering should be 5.0 ± 0.5 seconds.

6. Steer the machine from the left steering stop to the right steering stop as fast as possible. The speed of the steering should be 5.0 ± 0.5 seconds.