Check pressure oil pump of level control

AR32.31-P-0510A

Check pressure oil pump of level control

11.11.09



Removing

Danger!

Risk of injury to skin or eyes caused by hydraulic fluid spraying out under high pressure. Risk of poisoning caused by swallowing hydraulic fluid

Depressurize the hydraulic system completely before starting any work on the system. Wear protective clothing and safety glasses.

AS00.00-Z-0013-01A

1

Empty pressurized oil system on rear axle

AR32.31-P-0630A



Checking

2

Connect test equipment to connection piece (57) of rear axle



AR32.31-P-0510-01A

3

Pour oil into the oil reservoir (2)

 For the test increase the oil quantity to approx. 0.5 Ltr. above the "max" marking (a) on the oil dipstick (2a).

 Funnel

*126589126300

Oil as per Specifications for Operating Fluids-sheet 343

4

Disconnect return line (T) from oil reservoir (2), connect oil drain hose (061) to the return line (T) and guide into oil reservoir (2)

 For measuring delivery quantity of pressurized oil pump.

 Pay attention to safe hose routing. The oil pressure in the return increases to approx. 2 bar when the pressure relief valve in the valve unit is opened.

5

Connect handheld tester (089) to test socket with test cable (094)X11/4

AD00.00-P-1000AZ

Danger!

Risk of accident caused by vehicle starting off by itself when engine is running. Risk of injury caused by contusions and burns during starting procedure or when working near the engine as it is running

Secure vehicle to prevent it from moving by itself.
Wear closed and snug-fitting work clothes.
Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

6

Start engine and allow to idle

7

Handheld tester (089) in "Raise" position

8

Check delivery rate of pressurized oil pump

 Only perform test briefly due to high pressures.

 The delivery pressure of the pressurized oil pump is limited by the overflow valve in the valve unit.

Opening pressure of overflow valve

*BE32.31-P-1001-02A

when opening pressure in overflow valve is clearly dropped below 

and delivery rate at idle speed

*BE32.30-P-1002-02A

Replace pressurized oil pump/tandem pump

AR46.30-P-0500A

Too low pressure at optimum delivery quantity

Replace valve unit

AR32.31-P-0650A

9

Check delivery quantity of pressurized oil pump

Guide oil drain house (061) on return line (T) into a measuring vessel

 Ensure that there is sufficient oil in the oil reservoir. The pump must never draw in air under any circumstances.

In the delivery quantity is dropped below 

*BE32.30-P-1002-02A

Replace pressurized oil pump/tandem pump

AR46.30-P-0500A

If delivery quantity is exceeded 

and if the delivery rate is dropped below at idle speed 

*BE32.30-P-1002-02A

Replace valve unit

AR32.31-P-0650A

10

Turn off engine



Install

11

Disconnect handheld tester with test cable

AD00.00-P-1000AZ

Danger!

Risk of injury to skin or eyes caused by hydraulic fluid spraying out under high pressure. Risk of poisoning caused by swallowing hydraulic fluid

Depressurize the hydraulic system completely before starting any work on the system. Wear protective clothing and safety glasses.

AS00.00-Z-0013-01A

12

Disconnect test equipment on distributor fitting (57)

 

AR32.31-P-0510-01A

*BA32.31-P-1001-01A

13

Connect return line (T) to oil reservoir (2)

14

Fill pressurized oil system on front and rear axle

At the same time the front axle is also filled

AR32.31-P-0630A

Number

Designation

Model 129 with electronic level
control / ADS II

BE32.30-P-1002-02A

Delivery rate at idle speed

Liters/min

> 0.2

Number

Designation

Model 129 with electronic level control system / ADS II

BE32.31-P-1001-02A

Opening pressure of overflow valve

bar

180-190

Number

Designation

Model 129 with electronic level control system / ADS II

BA32.31-P-1001-01A

Oil drain screw on rear axle distributor fitting (reference value)

M101

Nm

14