EDGE 3998441 - Caterpillar

Personal injury or death can result if two persons are not used in the following procedure.
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, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products.Dispose of all fluids according to local regulations and mandates.
Machine Preparation
Prepare the machine for testing by completing the procedure that is specified in the Testing and Adjusting, "Machine Preparation for Troubleshooting" for the machine that is being serviced.Test Procedure
Brake service life can vary greatly because of the different applications. The following conditions can lead to premature brake failure:
Check for oil leaks at the yoke and the drive axles. A leak can also allow contamination from water and debris to occur. Water and debris can enter the axle through the lip seal at the drive yoke. The water and debris can mix with the oil. This water and debris can lead to premature brake failure.
The axle housing breather may be plugged or damaged. Check the axle housing breather for proper operation.
Excessive heat can be generated if the service brakes are used as a retarder. Excessive heat can be generated if the service brakes are used as a device to maintain a slower ground speed. This type of operation should be avoided by using a lower transmission gear speed. Check the grooves on both sides of each disc in both the front and rear service brakes. The wear of the service brake disc may vary from one end of the machine to the other end, and from one side of the machine to the other side. The estimated wear for a given groove depth is shown in table 1.It is important to change the friction discs as soon as possible once the groove depth has reached the maximum wear limit. As the depth of the grooves is reduced, the flow of the cooling oil is reduced. This causes heat to build up. The heat causes the rapid wear of the disc material. Eventually, the friction material will wear off the disc. This action will cause metal to metal contact between the disc and plates. This problem is known as spalling. The buildup of the friction material in the oil could cause damage to the smooth surface finish of the plate. Spalling will destroy the smooth surface finish of the plate. This action will make replacement of these brake components necessary. If the failure has progressed to metal to metal contact, thoroughly clean the complete axle. This process of cleaning the axle must be done correctly, or the debris will continue to contaminate the oil. This will cause the material on the service brake disc to wear rapidly. This condition will cause premature failure of the service brakes.If excessive brake wear or premature brake wear