12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Caterpillar


Hydraulic Pump

Usage:

Remove and Install Hydraulic Pump

Start By:

a. articulate the frame and install the anti-pivot pin.

b. remove pump drive

c. remove pressure and flow compensator valve

1. Remove four bolts (2) and disconnect elbow (3). Disconnect two hose assemblies (1), (one not shown).

2. Remove four bolts (5) and disconnect hose assembly (4) from hydraulic pump (6).

3. Disconnect hose assembly (7). Remove six bolts (8) and plate (12). Remove fitting (9) from the upper hitch pin. Remove four bolts and washers (10). Note: Keep shims between mount assembly (11) and the front frame.

4. Remove four bolts (13) and plate assembly (14) from hydraulic pump (6).

5. Fasten a hoist to hydraulic pump (6) and remove the pump from the machine. The weight of the hydraulic pump is 77 Kg (170 lbs.).

6. Remove nut (15) and yoke (16) from hydraulic pump (6). Note: Remove the woodruff Key from the shaft of the pump.

NOTE: The following steps are for installation of the hydraulic pump.

7. Apply 2P2506 Thread Lubricant on the taper and threads of the pump shaft. Install the woodruff key and yoke (16) on the pump shaft. Install nut (15) and torque the nut to 180 ± 14 N·m (135 ± 10 lb.ft.).

8. Position hydraulic pump on the front frame. Install plate assembly (14) and four bolts (13) on the hydraulic pump.

9. Put the shims between mount assemblies (11) and the front frame. Use shims as required to maintain 6 mm (.236 in.) clearance with the frame. Install four bolts and washers (10). Install plate (12) and six bolts (8). Install fitting (9) on the upper hitch pin. Connect hose assembly (7) to the hydraulic tank.

10. Position hose assembly (4) on hydraulic pump (6) and install four bolts (5).

11. Position hose assembly (3) on hydraulic pump (6) and install four bolts (2). Connect two hoses (1), (one not shown).

End By:

a. install pressure and flow compensator valve

b. install pump drive

c. remove anti-pivot pin from the main frames

Disassemble Hydraulic Pump

Start By:

a. remove implement pump

1. Remove fitting (3) from valve block (1).

2. Remove bolts (2) and remove valve block (1) from pump body (4). Remove the bias cylinder from the spring in the pump body. Remove the gasket from the pump body.

3. Remove stem (5), stem (6), pin (7) and check valve assembly (8) from the valve block (1).

4. Remove spring (10), water plate (9) and control cylinder (11).

5. Remove bearing assembly (12). Remove the spacers under bearing assembly (12).

6. Remove cylinder block (13) from shaft (14).

------ WARNING! ------

The spring located within the cylinder block is under high compression and can cause bodily harm, if caution is not used, if or when the retaining ring is removed.

--------WARNING!------

7. Carefully compress the spring with a press, and remove the retaining ring (15) with tool (B).

8. Remove spring washer (16), spring (17) and spring washer (18) from cylinder block (13).

9. Remove bolts (19) and cover (20) from pump body (4).

10. Remove key lock (21).

11. Remove piston and shoe assembly (22) from the pump body (4).

12. Remove bolts (23) and cover (24).

13. Remove O-ring seal (25), bearing spacer (26) and bearing (27).

14. Remove the O-ring seal, the bearing spacer and the bearing from the opposite side.

15. Remove shaft (14), swashplate (28) and the yoke and bumper assembly from the pump housing. Remove the bearing race from each side of pump body (4).

16. Remove bearing assembly (29).

17. Remove bearing race (30) and inner lip seal (31).

18. Remove outer lip seal (32).

Assemble Hydraulic Pump

NOTE: If new swashplate or bearings are installed, refer to topic, Hydraulic Pump/Swashplate Bearing in Specifications, Form No. SENR3488.

NOTE: If shaft, shaft bearing, head or housing is replaced refer to topic, Hydraulic Pump/Shaft Bearing Endplay in Specifications, Form No. SENR3488.

1. Install the inner and outer seals in the pump housing with tool group (A).

2. Lower the temperature of bearing race (30) and install it in pump housing (4).

3. Install bearing assembly (29).

4. Install the yoke and bumper assembly in the pump housing.

5. Follow the procedures below to provide the proper preload on the bearings.

6. Lower the temperature of the bearing race, and install it in the pump housing. Install bearing (27) and bearing spacer (26). Do not install the O-ring seal at this time.

7. Install cover (20) and tighten bolts (19) to a torque of 15 to 17 N·m (11 to 13 lb.ft.).

8. Turn the pump housing over. Lower the temperature of the bearing race, and install it in the pump housing. Install bearing (27) and bearing spacer (26). Do not install the O-ring seal at this time.

9. Rotate the yoke assembly back and forth to seat the bearings.

10. Measure the distance between the spacer and housing with a depth micrometer as shown.

11. Install the proper shim (33) to have a 0.25 to 0.40 mm (0.010 to 0.016 in.) axial preload. Install bearing spacer (26), O-ring seal, cover and bolts. Tighten the bolts to a torque of 15 to 17 N·m (11 to 13 lb.ft.).

12. Turn the housing over again, and remove the other cover and bolts. Install the O-ring seal, cover and bolts. Tighten the bolts to a torque of 15 to 17 N·m (11 to 13 lb.ft.).

13. Use a force indicator to push on the yoke pad as shown. The force required to start the swashplate moving should be 61 to 72 N (14 to 16 lb.). If the force is too low, shims (33) must be added. If the force is too high, shims (33) must be removed.

NOTE: 0.025 mm (.001 in.) shim thickness equals approximately 4.5 N (1 lb.) change in force.


NOTICE

Put tape around the splines on shaft (14) to avoid damaging the shaft seal when the shaft is installed.


14. Put shaft (14) in position in the housing.

15. Install swashplate (28), making sure the hole in the swashplate is in alignment with pin (34).

16. Install spring washer (16), spring (17) and spring washer (18) in the cylinder block (13). Install retaining ring (15) on top of spring washer (18).

17. Put the cylinder block assembly in a press.

18. Carefully compress the spring, and install the retainer ring with tool (B).

19. Install piston and shoe assembly (22) in the cylinder block.

20. Install the piston and cylinder block assembly in the pump housing.

21. Turn the cage shoe assembly so that key slot (35) will be in alignment when the key is installed.

22. Remove the bolts and covers, and install key (21).

23. Install cover and bolts. Tighten the bolts to a torque of 15 to 17 N·m (11 to 13 lb.ft.).

24. Install spacers (36) and bearing (12).

25. If the shaft bearings, shaft, valve block or housing was replaced, a bearing adjustment is necessary. Use the following procedures.

26. Lower the temperature of the bearing race, and install it in the valve block with tool group (A).

27. Install pin (7) and check valve (8).

28. Install the valve block on the housing, and hand tighten the bolts evenly. Measure the gap at four positions around the housing, and take the average reading. Also, measure the gasket thickness. With this measurement, determine the spacer or spacers necessary to obtain 0.00 to 0.100 mm (0.00 to 0.0039 in.) bearing end play. Remove the valve block (1) and bearing (12). Install correct spacer or spacers on shaft (14). Install bearing (12) on shaft (14).

29. Use Loctite no. 271 on threads. Install stems (5) and (6) in the valve block. Tighten the stems to a torque of 80 ± 4 N·m (60 ± 3 lb.ft.).

30. Install wafer plate (9) on the valve block, making sure the slot in the plate is in alignment with the pin in the valve block. Put clean grease on the plate to hold it in place.

31. Install spring (10), and bias cylinder on stem (6). Install control cylinder (11) on stem (5).

NOTE: Put clean grease in the cylinders to hold them in place for assembly.

32. Put valve block (1) and the gasket on pump body (4) and install bolts (2). Tighten bolts (2) to a torque of 50 to 55 N·m (37 to 41 lb.ft.).

33. Install fitting (3) on valve block (1).

End By:

a. install implement pump

Caterpillar Information System:

12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Pressure And Flow Compensator Valve
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Pump Drive
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Hydraulic Tank
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Circle Drive
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Circle Drive Motor
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Circle Drawbar
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Swivel Joint
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Blade Tip Cylinder
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Blade Centershift Cylinder
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Blade Sideshift Cylinder
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Centershift Lockplate Bushings
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Blade Lift Bar
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Hydraulic Control Valves
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Brake Control Valve
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Parking Brake Rotochamber And Release Valve
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Parking Brake Release Valve
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Differential Lock Actuator Valve
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Fuel Tank
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Articulation Cylinders
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Hydraulic Cylinders
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Main Frames
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Pivot Pin Bearings
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Rear Bumper
12G, 120G, 130G & 140G MOTOR GRADER VEHICLE SYSTEMS Blade Assembly
Back to top
The names Caterpillar, John Deere, JD, JCB, Hyundai or any other original equipment manufacturers are registered trademarks of the respective original equipment manufacturers. All names, descriptions, numbers and symbols are used for reference purposes only.
CH-Part.com is in no way associated with any of the manufacturers we have listed. All manufacturer's names and descriptions are for reference only.