Hydraulic Oil Pump Test

Hydraulic Test Program - Hydraulic Oil Pump Test

Preparation for Test
1. Check oil level in oil reservoir, correct if necessary.
2. Model 129
Unscrew connecting rods (54, 55) at front and rear leveling valve levers (set levers to neutral position).
Model 140
Unscrew connecting rod at leveling valve lever (3a).
3. Depressurize rear axle hydraulic system by slowly opening bleeder screw (3p). Connect drain hose and place into container.
4. Connect test gauge (038a) to rear axle leveling valve bleeder screw (82).
5. Model 129
Set both leveling valve levers to position "F" (fill).
6. Model 129
Open pressure supply screw (50a) by maximum of 1 turn.
7. Disconnect return line (T) at oil reservoir (2) and using a suitable hose, hold it in a measuring glass.

To perform this rest, the oil fill quantity must be increased by 0.5 liters. If the oil reservoir was empty, the hydraulic oil pump must first be bled by disconnecting the high pressure flexible hose at the steel line. Run the engine and hold the hose into a container until the oil exits free of bubbles.

Special Tools







Model 129



1 Hydraulic oil pump
2 Hydraulic oil reservoir
3 Rear axle levelling valve
3p Bleeder screw
6 Front axle leveling valve
6p Bleeder screw
50a Pressure supply screw
54 Front axle connecting rod
55 Rear axle connecting rod
T Return line - oil reservoir ditributor valve unit

Model 140



1 Hydraulic oil pump
2 Hydraulic oil reservoir
3 Rear axle leveling valve
3a Connecting lever
3p Bleeder screw
7 Rear axle connecting rod

Test: