GAUGE AS-SIGHT 2471076 - Caterpillar

Personal injury can result if the machine moves while testing.If the machine begins to move during test, reduce the engine speed immediately and engage the parking brake.
Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine.To prevent possible injury, perform the procedure that follows before testing and adjusting the brake system.
Illustration 1 g02571852
Tooling (A) 198-4240 Digital Pressure Indicator Gp
Table 1
Specifications
5688 345 kPa (825 50 psi)
Table 2
Required Tools
Tool Item Qty Part No Description
A 1 198-4240 Digital Pressure Indicator Gp
A A1 1 198-4234 Digital Indicator
A2 1 198-4238(1) Pressure Sensor Gp
(0 to 34,450 kPa (0 to 5,000 psi))
A3 1 198-4236 Adapter Cable As
(1) This sensor is not included in the 198-4240 Digital Pressure Indicator Gp and must be purchased separately.
Illustration 2 g02726620
Table 3
Required Tools
Tool Item Qty Part No Description
B B1 1 8T-0857 Pressure Gauge
(0 TO 10,000-KPA (0 TO 1,450-PSI))
B2 1 6V-3989 Fitting
B3 2 6V-4143 Quick Connect Coupler
B4 1 177-7860 Hose As
3.0 m (10 ft)
B4 1 177-7861 Hose As
4.3 m (14 ft)
B4 1 177-7862 Hose As
5.5 m (18 ft)
Stop the engine. Place the transmission Forward, Neutral, and Reverse (FNR) switch in the NEUTRAL position. Engage the parking brake.
Turn the keyswitch to the ON position.
Relieve the hydraulic oil pressure from the brake system by depressing the brake pedal repeatedly until there is no brake pressure.
Illustration 3 g02769418
The brake control valve is located directly below the brake pedal on the outside of the machine. Remove the cap from test port (1) for the front service brakes on the brake control valve (3). Install tooling (A) or tooling (B) to measure the pressure at test port (1).
Look at the pressure gauge. Before you start the engine, the hydraulic oil pressure should be 0 kPa (0 psi).
Start the engine. Allow the hydraulic oil to reach normal operating pressure and operating temperature.
Depress and hold down the brake pedal completely while monitoring the pressure gauge. The pressure must be within the specification listed in Table 1.
If the brake pressure did not meet specifications but the test for the accumulator met specifications, one of the following conditions exists:
The brake control valve is faulty.
Brake piston leakage is present in the brake system.Perform steps 1 through 8 using test port (2) to check the pressure for the rear brakes. The brake pressure test results for the rear brakes should be the same as listed above for the front brakes.Note: Measured pressure for the lower port will be around 200 kPa (29 psi) lower than the top port.