994H Wheel Loader Braking System Caterpillar

Illustration 1	g01142480

The rotation of the shaft is counterclockwise when the rotation of the shaft is viewed from the drive end.

Type: Pressure Compensated Variable Displacement Piston Pump

(1) Torque for the four screws ... 23 ± 2 N·m (205 ± 20 lb in)

(2) Install the washer with the square corner and the flat side toward the snap ring.

(3) 9T-4541 Spring

Free length after test ... 41.2 mm (1.62 inch)

Outside diameter ... 27.8 mm (1.09 inch)

(4) 4T-1916 Spring

Length under test force ... 42.1 mm (1.66 inch)

Test force ... 65.0 ± 6.5 N (14.61 ± 1.46 lb)

Free length after test ... 54.1 mm (2.13 inch)

Outside diameter ... 18.4 mm (0.73 inch)

Illustration 2	g02581597

(5) 4T-1909 Pressure Compensator Valve

(7) tighten to ... 9 ± 1 N·m (80 ± 8.9 lb in)

Pressure setting ... 16000 ± 345 kPa (2320 ± 50 psi)

(6) Torque for the four bolts ... 38 ± 4 N·m (28 ± 3 lb ft)

For the test, use SAE 10W oil that is at 46 ± 3°C (115 ± 5°F).

Test at full speed:

Output ... 32.2 L/min (8.5 US gpm)

Pressure ... 690 kPa (100 psi)

Pump speed ... 1710 rpm

Engine speed ... 1600 rpm

Output ... 31.8 L/min (8.4 US gpm)

Pressure ... 6900 kPa (1000 psi)

Pump speed ... 1710 rpm

Engine speed ... 1600 rpm

Test at half speed:

Output ... 15.1 L/min (4.0 US gpm)

Pressure ... 690 kPa (100 psi)

Pump speed ... 855 rpm

Engine speed ... 800 rpm

Output ... 14.9 L/min (3.9 US gpm)

Pressure ... 6900 kPa (1000 psi)

Pump speed ... 855 rpm

Engine speed ... 800 rpm

Illustration 3	g00013108
Cross-sectional view of (5) Pressure Compensator Valve

Pressure setting for the pressure compensator valve ... 16000 ± 345 kPa
(2320 ± 50 psi)

(1) 3G-5423 Spring

Test length ... 34.1 mm (1.34 inch)

Test force ... 560 ± 60 N (125 ± 13 lb)

Free length after test ... 39.9 mm (1.57 inch)

Outside diameter ... 16.1 mm (0.63 inch)

(2) Torque for nut ... 9 ± 1 N·m (80 ± 9 lb in)

Note: When you tighten nut (2), hold setscrew (3).