FILM 2897192 - Caterpillar

Table 1
Required Tools    
Part Number     Description    
198-4240     Digital Pressure Indicator    
Escaping fluid under pressure, even a pinhole size leak, can penetrate body tissue, causing serious injury, and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury.Always use a board or cardboard when checking for a leak.
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.
Illustration 1 g01200210
Location of the Brake Components (1) Pressure tap for rear service brake accumulator. (2) Parking brake control valve.
Illustration 2 g01200212
(3) Parking brake indicator. (4) Parking brake switch.
Remove the protective cap from pressure tap (1). Connect a 0 to 20700 kPa (0 to 3000 psi) pressure gauge at pressure tap (1) .
Start the engine and allow the accumulator oil pressure to increase to the cut-in pressure.Note: Keep the engine running. Allow the accumulator oil pressure to reach cutout pressure of 14485 345 kPa (2100 50 psi).
Push the bottom of parking brake switch (4). This will set the parking brake to the DISENGAGED position. Stop the engine.
Push the brake pedal rapidly several times until the parking brake engages. Parking brake indicator (3) will light.
Read the pressure on the gauge.
The correct hydraulic oil pressure should be 6035 515 kPa (875 75 psi). This will automatically engage the parking brake. If the pressure on the gauge is not correct, the operation of the parking brake control valve is not correct.
Inspect the parking brake control valve for worn parts or damaged parts. If these problems exist, replace the valve. Follow Steps 2 through 6 in order to recheck the brake system pressure.
Remove the test equipment.Note: If the machine is shut off with the parking brake in the DISENGAGED position, the parking brake will engage when the accumulator pressure falls. When the machine is restarted, Parking brake switch (4) must be cycled in order to disengage the parking brake. Push the top of the switch to the ENGAGE position. Push the bottom half of the switch. The brake will disengage.