ALTERNATOR GP-CHARGING 1420344 - Caterpillar

Illustration 1 g00632423
The pressure taps are located on the steering pump (1) . (2) Pressure tap. (3) Pressure tap for the load sensing oil.
Illustration 2 g00632415
Connect the high pressure port (8) of the 1U-5796 Pressure Differential Gauge Group (6) to the quick connect port at the pump discharge port (2). Install a 25000 kPa (3625 psi) pressure gauge (4) at the high pressure port (5) of the 1U-5796 Pressure Differential Gauge Group. Connect the low pressure port (7) of the 1U-5796 Pressure Differential Gauge Group (6) to the quick connect port at the pressure tap (3) of the load sensing line.Note: Two separate 6V-7830 Pressure Gauges can be used in place of the pressure differential gauge. These gauges are tetragauges. The tetragauges are capable of reading pressures from 0 to 40000 kPa (5801.6 psi). Connect one tetragauge to pressure tap (3). Connect the other tetragauge to pressure tap (2) .
Start the engine. Hold the bucket in the fully tilted back position while the engine is operating at high idle in order to warm the hydraulic oil. Hold the bucket in the tilted position until the reading on the hydraulic oil temperature gauge is between the first mark and the second mark.Note: Do not stall the bucket in the TILT position for more than ten seconds. If necessary, release for ten seconds and repeat the procedure.
Articulate the machine fully and engage the parking brake. Run the engine at high idle. Turn the steering wheel in the opposite direction of articulation. Hold the steering wheel in the fully turned position while the machine is articulating. The needle on the differential pressure gauge will bounce between readings. The needle should stabilize at 2800 100 kPa (406.1 14.5 psi) (steering pump margin pressure).Note: If you are using the tetragauges, the steering pump pressure should be 2800 100 kPa (406.1 14.5 psi) higher than the pressure in the load sensing line. This is the margin pressure. These pressures must be read during the articulation of the machine.
Illustration 3 g00640067
Stop the engine. Adjust the flow compensator valve if the pressure was not correct. Loosen locknut (9). Adjust setscrew (10) in order to adjust the setting of the steering pump margin pressure. Turn the setscrew clockwise in order to increase the margin pressure. Turn the setscrew counterclockwise in order to decrease the margin pressure.Reference: Refer to the Service Manual module Testing and Adjusting, "Piston Pump (Steering) Low Pressure Standby - Test and Adjust" for the machine that is being serviced.Note: If the margin pressure is set above the specification, the performance of the steering will become too responsive and jerky. Poor modulation will result. If the margin pressure is set below the specification, the performance of the steering will become sluggish and less responsive.