PLUG AS 3410087 - Caterpillar

Illustration 1 g00902215
(1) Steering piston pump
(2) Pressure and flow compensator valve
Illustration 2 g00902216
(1) Steering piston pump
(2) Pressure and flow compensator valve
(3) Pump drive
Illustration 3 g00902247
(4) Pressure tapThe following test covers the setting of pressure and flow compensator valve (2).Pressure compensator valve (2) is mounted to the steering pump (1). The steering pump (1) is mounted to the pump drive (3). Pump drive (3) is on the inside right frame rail near the torque converter.The pressure setting of the pressure compensator valve (1) is 17580 345 kPa (2550 50 psi).To check the pressure setting of pressure compensator valve (2), use the following procedure:
Illustration 4 g00902258
Remove the cap from pressure tap (4). Pressure tap (4) is on the steering accumulator.
Install a 8T-0859 Pressure Gauge on pressure tap (4).
Start the engine and operate the engine at low idle.
The pressure reading on the gauge should go up to 17580 345 kPa (2550 50 psi).
Stop the engine. If the setting of pressure compensator valve (2) is incorrect, remove nut (5).
Loosen nut (6).
If the pressure setting for pressure and flow compensator valve (2) is low, slowly rotate pressure adjusting screw (7) clockwise to increase the pressure until the proper pressure is attained.Note: Each 1/4 turn of pressure adjusting screw (7) changes the pressure approximately 1241 kPa (180 psi) to 1723 kPa (250 psi).
If the pressure setting for pressure and flow compensator valve (2) is high, slowly rotate pressure adjusting screw (7) counterclockwise to decrease the pressure until the proper pressure is attained.Note: Each 1/4 turn of pressure adjusting screw (7) changes the pressure approximately 1241 kPa (180 psi) to 1723 kPa (250 psi).
Tighten nut (6) to 21 N m (15 lb ft).
Tighten nut (5) to 21 N m (15 lb ft).
Remove the test equipment and replace the cap on pressure tap (4).Leakage
A leakage oil test for the condition of the steering pump is made on a hydraulic test bench. The Leakage Oil Chart has the information that is needed for the test.The steering pump has too much wear if the leakage oil is more than the value found on the Leakage Oil Chart and the pump output is less than the value found on the Leakage Oil Chart.
Table 1
Leakage Oil Chart
Hydraulic Oil Temperature 63° to 68°C (145° to 155°F)
Pump rpm Approximate Oil Pressure Pump Output Leakage Oil
1900 3450 kPa (500 psi) 128 L/min (34 US gpm) 8.4 L/min (2.22 US gpm)
1900 10300 kPa (1494 psi) 124 L/min (33 US gpm) 11.0 L/min (2.91 US gpm)
1900 15900 kPa (2306 psi) 120 L/min (32 US gpm) 13.6 L/min (3.59 US gpm)
1900 17200 kPa (2495 psi) 0 L/min (0 US gpm) 14.0 L/min (3.70 US gpm)