DAF CF65, CF75, CF85 Series . Manual - part 947

©

 200423

1-7

Steering gear, general

DIAGNOSTICS

ΧΦ65/75/85 series

7

1

SYMPTOM: VIBRATIONS IN THE STEERING WHEEL

Possible cause

Remedy

Dirt between wheel rim and hub

Remove wheel and clean wheel rim and hub.

Install wheel as specified.

Wheel nuts have not been tightened evenly

Loosen all nuts and tighten these as specified.

Wheel imbalance

Balance wheel statically and dynamically.

SYMPTOM: AIR IN THE STEERING OIL

Possible cause

Remedy

Reservoir oil level too low

Check the oil level.

Top up oil.

Check for leakage.

Poor sealing of the supply line connections.

Check connections.

Replace the hose with the clamps.

Porous supply line

Replace the hose with the clamps.

Poor internal sealing of the steering pump

Replace steering pump.

SYMPTOM: STEERING OIL LEAKAGE

Possible cause

Remedy

Leaking delivery or return line.

Leaking delivery or return line connection.

Leaking reservoir connection pipe

Check the lines and line connections.

Tighten the lines securely.

Replace the line.

Leaking reservoir

Replace reservoir.

Leaking steering pump

Check sealing of the pump housing at the main 

steering pump and sealing of the plug at the rear of 

the steering pump.

Check sealing of the pump housing at the 

emergency steering pump, the sealing of the plugs 

at the pump housing and the sealing of the plug at 

the rear of the pump.

Replace the O-ring concerned.

DIAGNOSTICS

1-8

©

 200423

Steering gear, general

1

ΧΦ65/75/85 series

7

SOUND

Leaking steering box

On the steering box, check the following seals:

-

input shaft oil seal

-

sector shaft oil seal in side cover (plastic plug)

-

side cover gasket

-

valve housing/cylinder

-

sector shaft on pitman arm side

-

various plugs

-

adjusting bolt of wheel deflection limiting 

valves

Depending on the leak, replace the input shaft oil 

seal, the sector shaft oil seals, the side cover 

gasket, and the sealing rings of the various plugs 

and the adjusting bolt.

Replace the steering box in the case of leaks other 

than described above.

The melting point of the grease found behind the 

dust seal of the sector shaft or the input shaft is too 

low.

It seems like the steering box is leaking, but in fact 

the grease has melted.

Replace the grease with grease of the specified 

type (melting point >130

C).

Note:

The steering gear always produces sounds.

Normal sounds:

-

a hissing sound in the steering box while steering. The sound level depends on the system pressure.

-

an increasing sound level when opening the wheel deflection limiting valve.

-

a maximum sound level when opening the pressure-limiting valve.

-

the emergency steering pump (plunger pump) produces a considerably higher sound level than the 

main steering pump (vane pump).

SYMPTOM: STEERING PUMP PRODUCES A SQUEALING SOUND WHILE STEERING

Possible cause

Remedy

Oil level too low, causing the pump to draw air.

Check the oil level.

Top up oil and check for leaks.

Air in the steering oil

Check oil for the presence of air (foaming).

Bleed system and find the cause.

Supply line kinked or pinched off.

Check the supply line.

The supply opening in the reservoir is (partially) 

blocked.

Check supply opening in the reservoir.

SYMPTOM: STEERING OIL LEAKAGE

Possible cause

Remedy

©

 200423

1-9

Steering gear, general

DIAGNOSTICS

ΧΦ65/75/85 series

7

1

SYMPTOM: THE STEERING PUMP PRODUCES A DIFFERENT SOUND WHEN AT IDLING SPEED. 

THE SOUND LEVEL INCREASES WHEN THE ENGINE SPEED INCREASES

Possible cause

Remedy

Worn steering pump

Replace steering pump.

Replace steering oil.

Clean the reservoir and lines.

Replace filter.

SYMPTOM: WHEN STEERING THE SOUND OF METAL SCRAPING AGAINST METAL IS HEARD

Possible cause

Remedy

Loose steering box, steering bracket or pitman arm Check attachment of components.

Tighten bolts to the specified tightening torque.

Play in a steering rod or track rod ball joint.

Check ball joints.

Replace ball joint.

There is friction between the steering gear 

components.

Turn steering gear carefully from one stop to the 

other and check the mechanical part of the 

steering gear for friction.

Play of the steering column slide joint

Check slide joint for wear.

Replace slide joint.

DIAGNOSTICS

1-10

©

 200423

Steering gear, general

1

ΧΦ65/75/85 series

7