ROLLER AS 4777938 - Caterpillar

Personal injury or death can result from sudden machine movement.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 fluids.Refer to Special Publication, NENG2500, "Caterpillar Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products.Dispose of all fluids according to local regulations and mandates.
This section provides probable causes to known problems. Perform a visual inspection of the machine. Refer to Testing and Adjusting, "Visual Inspection". Prepare the machine for troubleshooting. Refer to Testing and Adjusting, "Machine Preparation for Troubleshooting".Operational Checks
Operate the machine in each direction and in all speeds. Note the noises that are not normal and find the sources of the noises. If the machine is not operating correctly, refer to "Troubleshooting Problem List".Troubleshooting Problem List
Problem List For The Service Brake
The service brake does not operate.
The indicator light for low brake fluid level is on.
The service brake slips.
Too much force needed to push the brake pedal.
The service brake pressure (SB) fails to reach the minimum pressure.
The service brake pedal is soft.Problem List For The Parking Brake
The parking brake does not hold the machine stationary.
The parking brake does not engage when the parking brake control lever is actuated.
The alert indicator for the parking brake will not turn on.
The alert indicator for the parking brake will not turn off.Troubleshooting Probable Causes
Probable Causes To Problems Of The Service Brake
Problem 1The service brake does not operate.Probable causes
The lines to the service brakes could be obstructed. Visually inspect the lines.
The service brake control could be damaged. Inspect the service brake control. Refer to the Testing and Adjusting, "Service Brake - Test and Adjust".Problem 2The indicator light for low brake fluid level is on.Probable causes
The speed sensing valve might not be supplying oil to the master cylinder. Test the speed sensing valve. Refer to the Testing and Adjusting, "Hydrostatic System - Test and Adjust".
The liquid level sensor could be malfunctioning. Replace the liquid level sensor.
There could be a malfunction in the electrical system. Refer to the Electrical System Schematic, RENR2838.Problem 3The service brake slips.Probable causes
The brake discs could be worn. Inspect the brake discs. Replace the disk when the thickness becomes less than 8.30 mm (0.33 inch). Refer to the Disassembly and Assembly, RENR2831, "Axle Planetary and Brake Piston (Front) - Remove".
There could be air in the brake lines. Purge the air from the service brakes. Refer to the Testing and Adjusting, "Braking System Air - Purge".Problem 4Too much force needed to push the brake pedal.Probable causes
The service brake control could be worn or damaged. Adjust the service brake control. Refer to the Testing and Adjusting, "Service Brake - Test