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LOCATION:    3.1 Adaptive Damping System (ADS)   >   32 Hydraulic Test Program - 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. Unscrew connecting rods (54, 55) at front and rear leveling valve levers (set levers to neutral position).
3. Depressurize rear axle hydraulic system by slowly opening bleeder screw (3p). Connect drain hose and place into container.
4. Connect test gauge to rear axle leveling valve bleeder screw (S2).
5. Set both leveling valve levers to position "F" (fill).
6. 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.

Test step
Test scope
Test connection
Test condition
Nominal value
Possible cause/Remedy 1)
1.0 Delivery pressure

WARNING!
High pressure
250 bar
Connect test gague to rear axle leveling valve connection S2
Engine: at Idle
Set leveling valve lever(s) to position "F" (fill).
Observe test gauge needle until pressure no longer increases.
> 133 bar

Delivery capacity at idle
> 0.2 l/min.
Delivery pressure < 133 bar,
Delivery capacity < 0.2 l/min:
Replace hydraulic oil pressure pump
(SMS, Job No. 32-640)

Delivery pressure < 133 bar,
Delivery capacity > 0.2 l/min:
see 34
1) Observe Preparation for Test, see 22.