CONTROL AR- 4877677 - Caterpillar

Introduction
This information includes the following tests:
Discharging the Accumulator
Testing Procedure for the Accumulator Pre charge Pressure
Charging Procedure
Brake Accumulator Pressure TestRequired Tools
Illustration 1 g03602148
Table 2
Required Tools
Tool Item Qty Part No Description
B B1 1 8T-0862 Pressure Gauge
(-100 TO 500-KPA (-15 TO 72-PSI))
B1 1 8T-0863 Pressure Gauge
(0 TO 250-KPA (0 TO 36-PSI))
B1 1 8T-0853 Pressure Gauge
(0 TO 400-KPA (0 TO 58-PSI))
B1 1 8T-0854 Pressure Gauge
(0 TO 1,000-KPA (0 TO 145-PSI))
B1 1 8T-0855 Pressure Gauge
(0 TO 4,000-KPA (0 TO 580-PSI))
B1 1 8T0-8656 Pressure Gauge
(0 TO 6,000-KPA (0 TO 970-PSI))
B1 1 8T-0857 Pressure Gauge
(0 TO 10,000-KPA (0 TO 1,450-PSI))
B1 1 8T-0858 Pressure Gauge
(0 TO 16,000-KPA (0 TO 2,300-PSI))
B1 1 8T-0859 Pressure Gauge
(0 TO 25,000-KPA (0 TO 3,600-PSI))
B1 1 8T-0860 Pressure Gauge
(0 TO 40,000-KPA (0 TO 5,800-PSI))
B1 1 8T-0861 Pressure Gauge
(0 TO 60,000-KPA (0 TO 8,700-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) Machine Preparation
Prepare the machine for testing refer to Testing and Adjusting, "Machine Preparation for Testing and Adjusting" for the machine that is being serviced.Refer to Testing and Adjusting, "System Pressure - Release" to relieve hydraulic system pressure.Discharging the Accumulator
Refer to Special Instruction, REHS5464, "Accumulator Discharging and Charging Procedures" for the required tooling, and the testing and charging procedure.Testing Procedure for the Accumulator Pre charge Pressure
Refer to Special Instruction, REHS5464, "Accumulator Discharging and Charging Procedures" for the required tooling, and the testing and charging procedure.Charging Procedure
Refer to Special Instruction, REHS5464, "Accumulator Discharging and Charging Procedures" for the required tooling, and the testing and charging procedure.Brake Accumulator Pressure-Test
Move the machine to smooth, level ground that will support the weight of the machine.
Stop the machine
Engage the steering frame lock.
Apply the parking brake.
Illustration 2 g03602246
View of front brake accumulator test tap. Brake accumulator test taps can be accessed from the left-hand side of the machine.
Illustration 3 g03602536
View of the rear brake accumulator test tap.
Attach tooling (B) using the appropriate gauge onto the front brake accumulator test tap.
Release pressure on accumulators by fully depressing the brake pedal between 37 to 40 times until you feel the brake pressure drop.
Start the engine and bring Hydraulic fluid to operating temperature.
Repeatedly depress and release the brake pedal until the brakes cut in. The minimum measured pressure in the accumulators is the cut in pressure.
Record the cut in pressure.
Continue to apply and release the brake pedal until a second cut in occurs and until the pressure ceases to rise. This cut in should happen within five to seven strokes. The maximum recordable pressure in the accumulators is the cut out pressure.
Record the cut out pressure.
Compare the recorded pressures to the pressures in Table 1
Repeat Step 5 through Step 12to check pressure for the rear brake accumulator.
If, the pressures for the brake accumulators are within specifications remove tooling.
If, pressures are not