527 Track-Type Skidder Hydraulic System Caterpillar

Illustration 1	g00447085

For the bench test, use SAE 10W oil at 65°C (149°F).

Pump type ... Variable piston

Rotation ... Counterclockwise

Functional Requirements

Output ... 111 ± 6 L (29 ± 1.6 US gal)

Output pressure ... 7000 kPa (1015 psi)

Pump speed ... 2200 rpm

Engine speed ... 2200 rpm

Compensator Valve

Pump pressure cutoff (zero flow) ... 20700 ± 350 kPa (3000 ± 50 psi)

Margin pressure

Setting ... 1700 ± 100 kPa (247 ± 15 psi)

Flow rate ... 55 L/min (15 US gpm)

Discharge pressure ... 15000 kPa (2175.6 psi)

Maximum standby pressure ... 3200 kPa (464 psi)

(1) Torque for plug ... 102 ± 5 N·m (75 ± 4 lb ft)

(2) Torque for four screws ... 33 ± 3 N·m (24.3 ± 2.2 lb ft)

(3) Torque for three screws ... 8.5 ± 1.0 N·m (75.23 ± 8.85 lb in)

(4) Torque for two screws ... 4.0 ± 0.4 N·m (35.40 ± 3.54 lb in)

(5) Torque for plug ... 79 ± 4 N·m (58.3 ± 3.0 lb ft)

(6) Torque for two bolts ... 71 ± 14 N·m (52.4 ± 10.3 lb ft)

(7) Torque for four bolts ... 34 ± 3 N·m (25.1 ± 2.2 lb ft)

(8) Torque for four bolts ... 71 ± 14 N·m (52.4 ± 10.3 lb ft)

(10) Put 9S-3263 Thread Lock Compound on the threads. Tighten the rod to the following torque. ... 79 ± 4 N·m (58.3 ± 3.0 lb ft)

(11) 6E-6579 Bias Spring

Length of test force ... 74.36 mm (2.927 inch)

Test force ... 717 ± 72 N (161.2 ± 16.2 lb)

Free length after test ... 126.0 mm (4.96 inch)

Outside diameter ... 37.26 mm (1.467 inch)

(12) Torque for four plugs ... 12.8 ± 0.2 N·m (113.29 ± 1.77 lb in)

(15) Use shims in order to obtain the following end play. ... 0.01 to 0.10 mm (0.004 to 0.04 inch)

(16) 9T-1699 Spring

Length under test force ... 11.10 mm (0.437 inch)

Test force ... 32.60 ± 3.11 N (7.329 ± 0.699 lb)

Free length after test ... 17.17 mm (0.676 inch)

Outside diameter ... 24.89 mm (0.980 inch)

(18) Put 9S-3263 Thread Lock Compound on the threads. Tighten the rod to the following torque. ... 79 ± 4 N·m (58.3 ± 3.0 lb ft)

Shaft Bearing End Play Adjustment

1. Perform this procedure when the shaft bearing, the shaft, the head, or the housing is replaced.

   Note: Do not install the barrel assembly or the pistons for this procedure.

2. Remove control cylinder (17), bias cylinder (9), and bias spring (11) from head (14) .

3. Install bearing cone (19) on the splined end of shaft (21). Install the bearing cup in housing (20). Make sure that the cup and the cone are against each location shoulder.

4. Install the shaft and the bearing cone into housing (20) .

5. Install bearing cone (13) on shaft (21) without shims (15). Install the bearing cup in head (14). Make sure that the cup and the cone are against each location shoulder.

6. Assemble head (14) to housing (20) with the gasket in place.

7. Tighten six bolts (6) and (8) to a torque of 71 ± 14 N·m (52.4 ± 10.3 lb ft).

   Note: Two of the bolts are replaced by studs in order to assist in aligning the head and the housing for assembly.

8. Position the pump so that shaft (21) is vertical with the splined end at the top.

9. Rotate shaft (21) backward and forward several times in order to seat the bearings.

10. Place a dial indicator so that the tip of the indicator is on the end of shaft (21). Read the dial indicator while the shaft is under upward force.

11. Subtract the desired end play of 0.064 ± 0.038 mm (0.0025 ± 0.0015 inch) from the dimension that is measured in Step 10.
    Show/hide table

    Table 1

    Example
    End play from Step 10	1.016 mm (0.0400 inch)
    Minus desired end play	0.064 ± 0.038 mm (0.0025 ± 0.0015 inch)
    Required thickness of shim	0.952 ± 0.038 mm (0.0375 ± 0.0015 inch)

12. Remove six bolts (6) and (8). Then remove head (14) from housing (20) .

13. Remove bearing cone (13) from shaft (21) .

14. Install the correct thickness of shims (15) from Step 11 on shaft (21). Then reinstall bearing cone (13) .

15. Repeat Step 6 through Step 10. If the measured end play is not 0.025 to 0.100 mm (0.001 to 0.004 inch), repeat Step 11 through Step 15.