MAGNETO GP 7W2172 - Caterpillar

Table 1
Required Tools
Part Number Part Description Qty
4C-4890 Hydraulic Test Group 1
Move the transmission control to the NEUTRAL position and move the parking brake control to the ENGAGED position. Shut off the engine.
Install the steering frame lock. Refer to Operation and Maintenance Manual, "Steering Frame Lock".
Illustration 1 g03531389
(15) Rear service brake accumulator
(16) Front service brake accumulator
(T3) Front service brake pressure test port
(T4) Rear service brake pressure test port
Connect a 20690 kPa (3000 psi) pressure gauge to the test point (T4).
Start the engine. Operate the engine at low idle for 1 minute to charge the service brake system.
Press the brake pedal and read the pressure on the gauge. The gauge should show 4619.5 172.4 kPa (670 25 psi) on the 725C2 and 5240 172.4 kPa (760 25 psi) on the 730C2 and 730C2 EJ Articulated Trucks.If the pressure is incorrect, there may be a problem with the service brake control valve.
Release the brake pedal and observe the fall of the brake pressure. The pressure should fall below 30 kPa (4 psi). Residual pressure above this value can cause brake drag.If residual pressure occurs in the braking system, there may be a problem with the service brake control valve. Also, the braking system may require purging. Refer to Testing and Adjusting, "Service Brake Air - Purge".
Shut off the engine. Remove the pressure gauge and the steering frame lock from the machine. Refer to Operation and Maintenance Manual, "Steering Frame Lock".