Check and adjust hydraulic steering limiter

AR46.20-W-1100G

Check and adjust hydraulic steering limiter

08.11.2019

Model

970, 972, 974, 975, 976

SteeringZF8097

Vehicles with elbow fitting

1

Steering gear

2

Elbow fitting (without test connection)

3

Elbow fitting (with test connection)

3.1

Screw plug

Vehicles with threaded fitting or swivel fitting

7

Oil pressure hose

8

Oil pressure line

13

Adapter

13.1

Screw plug

3

Elbow fitting (with test connection)

3.1

Screw plug

4

Test connection

5

Hose

6

Pressure gage

13

Adapter

13.1

Screw plug

1

Steering gear

15

Adjustment screw (for left hydraulic steering limiter on left-hand drive vehicles; for right hydraulic steering limiter on right-hand drive vehicles)

1

Steering gear

16

Adjustment screw (for right hydraulic steering limiter on left-hand drive vehicles; for left hydraulic steering limiter on right-hand drive vehicles)

17

Sliding bush

 Danger

Risk of death caused by vehicle slipping or toppling off during lifting

Only lift vehicle at the lift support points specified by the vehicle manufacturer.

AS00.00-Z-0032-01A

 Warning

Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.

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

AS00.00-Z-0005-01A

 Warning

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

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

AS00.00-Z-0013-01A

 Warning

Risk of injury from being trapped in the swivel range of steered axles

Ensure that no persons or objects are in the swivel range of all steered axles when turning the steering wheel. Do not stand in the swivel range of the additional steering axle when the engine is running.

AS46.00-Z-0002-01A

 Warning

Risk of injury to skin or eyes from hot hydraulic fluid spraying out under high pressure. Risk of burn injuries from contact with components heated by hot hydraulic fluid. Risk of poisoning from swallowing hydraulic fluid

Do not make any technical modifications to the pressure gauge or the test equipment. Check the pressure gauge and test equipment for mechanical damage each time prior to use. Observe the flow diagram when connecting the test equipment. Wear protective gloves, protective clothing and safety glasses.

AS46.00-Z-0003-01A

 Warning

Risk of accident and injury caused by diagnostic equipment in vehicle while traveling

Never use the test equipment to verify the delivery rate and oil pressure of the power steering pump or the pressure gauge while driving.

AS58.40-Z-0001-01B

 Warning

Risk of injury caused by body parts being pinched or crushed as cab is tilted

Ensure that no one is within the tilting range of the cab as it is being tilted. Always tilt the cab all the way to the end position and secure it with the safety strut.

AS60.80-Z-0001-01A

Topical note

Special instructions for lifting and supporting vehicle

AH00.60-N-0100-01B

Topical note

Notes on maintenance and repair work

AH46.20-N-0001-01H

Topical note

Notes on tilting the cab

AH60.80-N-0003-01A

Note on calculation of tightening torque when using insertion or socket tools with various effective lengths

AH00.00-P-0015-01CW



Check

1.1

Move vehicle to driving level using level control system operating unit.

On vehicles with code A00 (Air-sprung front axle)

1.2

Load vehicle so as to be as close to primary operating conditions as possible.

On vehicles without code A00 (Air-sprung front axle)

 In isolated cases, and as a result of the steering kinematics, a front axle load that is too low may result in the steering limitation adjustment pressure not being reached or in adjustment not being possible.

2

Move front wheels to straight-ahead position.

3

Secure vehicle to prevent it moving away.

4

Tilt cab.

5

Remove boot from steering gear.

6.1

Replace elbow fitting (2) with elbow fitting (3).

On vehicles in which elbow fitting (2) is installed.

 The elbow fitting (3) can be ordered using part number A 004 997 19 71 and it remains installed after the test.
Collect escaping oil in suitable container.

 Union nut, steering gear oil line/hose

*BA46.25-N-1001-04B

 Oil pressure line fitting to steering gear

*BA46.20-N-1009-01FB

6.2

Install adapter (13) between oil pressure hose (7) and oil pressure line (8).

On vehicles in which a threaded or swivel fitting is installed.

 Collect escaping oil in suitable container.

 Union nut, steering gear oil line/hose

*BA46.25-N-1001-04B

 Adapter

*967589009100

7.1

Unscrew screw plug (3.1) from elbow fitting (3).

On vehicles in which elbow fitting (3) is installed.

 Collect escaping oil in suitable container.

7.2

Unscrew screw plug (13.1) from adapter (13).

On vehicles in which adapter (13) was installed.

 Collect escaping oil in suitable container.

8

Install test connection (4).

 The test connection (4) can be ordered using part number A 942 351 00 69.

 Test connection to adapter

*BA46.20-N-1005-01FB

 Test connection to elbow fitting

*BA46.20-N-1011-01FB

9

Connect hose (5) to manometer (6).

 Pressure gage

*000589062100

 Hose

*400589019100

10

Unscrew cap from test connection (4).

11

Connect hose (5) to test connection (4).

12

Fill and bleed steering gear oil.

AR46.25-W-3001G

 Leave front axle raised after bleeding.
Ensure that hose (5) and manometer (6) are not trapped when cab is finally tilted back.

13

Position front wheels centrally on turn plates.

AR00.60-W-2000-01H

14

Start engine and run at idle speed.

15

Turn steering to left or right several times using normal force of the hand until a steering gear oil temperature of approx. 50 °C is reached in the steering.


Only pull against mechanical end stop at steering wheel circumference for a short period of time (max. 5 s).
Otherwise damage could occur to the steering system.

16

Turn steering wheel left up to mechanical end stop using normal force of the hand, read off pressure at manomenter (6), and release steering wheel again.


Only pull against mechanical end stop at steering wheel circumference for a short period of time (max. 5 s).
Otherwise damage could occur to the steering system.

17

Note down measured pressure.

18

Turn steering wheel to right up to mechanical end stop using normal force of the hand, read off pressure at manometer (6), and release steering wheel again.


Only pull against mechanical end stop at steering wheel circumference for a short period of time (max. 5 s).
Otherwise damage could occur to the steering system.

19

Note down measured pressure.

20

Move front wheels to straight-ahead position.

21

Switch off engine.

22

Compare noted pressures with specified adjustment pressure of steering limitation valves.

Adjustment pressure for steering limiter

*BE46.20-N-1002-01FB

If the noted pressures do not match with specified adjustment pressure of steering limitation valves:



Tilt cab and replace setting screws (15, 16).

 Collect escaping oil in suitable container.

 Adjustment bolt of automatically-adjusting hydraulic steering limiter in steering gear

*BA46.20-N-1004-01FB

23

Tilt cab.

Only if cab was not already tilted to replace setting screws (15, 16).

24

Detach hose (5) from test connection (4).

 Collect escaping oil in suitable container.

25

Screw cap onto test connection (4).

26

Detach hose (5) from manometer (6) and seal all connections.

27

Remove test connection (4).

 Collect escaping oil in suitable container.

28.1

Screw screw plug (3.1) into elbow fitting (3).

On vehicles with elbow fitting (3).

 Screw plug to elbow fitting

*BA46.20-N-1012-01FB

28.2

Screw screw plug (13.1) into adapter (13).

On vehicles in which adapter (13) was installed.

 Screw plug to adapter

*BA46.20-N-1006-01FB

29

Remove adapter (13) and attach oil pressure hose (7) to oil pressure line (8).

If adapter (13) was necessary for the test.

 Collect escaping oil in suitable container.

 Union nut, steering gear oil line/hose

*BA46.25-N-1001-04B

30

Attach boot to steering gear.

31

Fill and bleed steering gear oil.

AR46.25-W-3001G

 Turning the steering wheel to both the left and right end stop causes the sliding bushings (17) on the setting screws (15, 16) to be automatically moved to the switch-off position.
During the adjustment procedure, increased force must be applied to the steering wheel when turning the steering both mechanically and with hydraulic assistance.
After bleeding, remove all turn plates, lower vehicle back onto floor, and tilt cab back.

32

Conduct a road test.

 During the test drive, check the overall steering ability of the vehicle.

33

Check steering gear (1) or connecting point between oil pressure line (8) and oil pressure hose (7) for leak tightness.

 Visual inspection.

Test values for steering gear

Number

Designation

Steering ZF8097 in model 972, 974, 975, 976 (Left-hand drive vehicle),
steering ZF8097 in model 970 (Left-hand drive vehicle) without code A00

Steering ZF8097 in model 972, 974, 975, 976 (Right-hand drive vehicle),
steering ZF8097 in model 970 (Right-hand drive vehicle) without code A00

BE46.20-N-1002-01FB

Adjustment pressure for steering limiter

Vehicle unladen

Steering to left

Specified value

bar

50 (+10)

30 (+10)

at engine speed

1/min

 800

 800

Steering to right

Specified value

bar

30 (+10)

50 (+10)

at engine speed

1/min

 800

 800

Load vehicle

Steering to left

Specified value

bar

40 (+10)

40 (+10)

at engine speed

1/min

 800

 800

Steering to right

Specified value

bar

40 (+10)

40 (+10)

at engine speed

1/min

 800

 800

Test values for steering gear

Number

Designation

Steering ZF8097 in model 970 with code A00

BE46.20-N-1002-01FB

Adjustment pressure for steering limiter

Vehicle unladen

Steering to left

Specified value

bar

40 (+10)

at engine speed

1/min

 800

Steering to right

Specified value

bar

40 (+10)

at engine speed

1/min

 800

Load vehicle

Steering to left

Specified value

bar

40 (+10)

at engine speed

1/min

 800

Steering to right

Specified value

bar

40 (+10)

at engine speed

1/min

 800

 Steering gear

Number

Designation

SteeringZF8097

BA46.20-N-1004-01FB

Adjustment bolt of automatically-adjusting hydraulic steering limiter in steering gear

Nm

20

 Steering gear

Number

Designation

SteeringZF8097

BA46.20-N-1005-01FB

Test connection to adapter

Nm

14

 Steering gear

Number

Designation

SteeringZF8097

BA46.20-N-1006-01FB

Screw plug to adapter

Nm

18

 Steering gear

Number

Designation

SteeringZF8097

BA46.20-N-1009-01FB

Oil pressure line fitting to steering gear

Nm

60

 Steering gear

Number

Designation

SteeringZF8097

BA46.20-N-1011-01FB

Test connection to elbow fitting

Nm

14

 Steering gear

Number

Designation

SteeringZF8097

BA46.20-N-1012-01FB

Screw plug to elbow fitting

Nm

18

 Hydraulic power steering

Number

Designation

Model 375.1, 958, 970, 972, 974, 975, 976

BA46.25-N-1001-04B

Union nut, steering gear oil line/hose

Line Ø 12 mm

Nm

50

Line Ø 15 mm

Nm

60