DAF 95XF. Manual - part 383

4

DIAGNOSIS

XF engine inlet and exhaust system

95

XF series

3-2

FAULT: RISING AND FALLING TURBOCHARGER SOUNDS

Possible cause

Remedy

Blocked air inlet to turbocharger.

Check air inlet and remove any obstacles.

Compressor side of turbocharger contaminated.

Clean compressor side with a non-corrosive
cleaning agent or a soft brush. Check the inlet
side for carbon deposits or other contamination.

Damaged turbocharger.

Replace turbocharger and identify the cause.

FAULT: BLACK SMOKE EMERGING FROM EXHAUST

Possible cause

Remedy

Air cleaner element blocked.

Clean or replace air cleaner element.

Air leak between turbocharger and inlet
manifold.

Check pipes and pressurise inlet unit.

Air leak between inlet manifold and cylinder
head.

Check for leaks. Replace gaskets, if necessary.

Compressor side of turbocharger contaminated.

Clean compressor side with a non-corrosive
cleaning agent or a soft brush. Check the inlet
side for carbon deposits or other contamination.

Gas leak between exhaust manifold and cylinder
head.

Check attachment bolts and gaskets.

Gas leak between exhaust manifold and
turbocharger.

Check attachment bolts and gaskets.

Damaged turbocharger.

Replace turbocharger and identify the cause.

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4

95

XF series

XF engine inlet and exhaust system

DIAGNOSIS

3-3

FAULT: BLUE SMOKE EMERGING FROM EXHAUST

Possible cause

Remedy

Air cleaner element blocked.

Clean or replace air cleaner element.

Air leak between turbocharger and inlet
manifold.

Check pipes and pressurise inlet unit.

Air leak between inlet manifold and cylinder
head.

Check for leaks. Replace gaskets, if necessary.

Compressor side of turbocharger contaminated.

Clean compressor side with a non-corrosive
cleaning agent or a soft brush. Check the inlet
side for carbon deposits or other contamination.

Turbocharger oil discharge pipe is blocked.

Check oil pipe. Replace if necessary.

Damaged turbocharger.

Replace turbocharger and identify the cause.

FAULT: OIL LEAK AT TURBINE SIDE OF TURBOCHARGER

Possible cause

Remedy

Compressor side of turbocharger contaminated.

Clean compressor side with a non-corrosive
cleaning agent or a soft brush. Check the inlet
side for carbon deposits or other contamination.

Turbocharger oil discharge pipe is blocked.

Check oil pipe. Replace if necessary.

Damaged turbocharger.

Replace turbocharger and identify the cause.

FAULT: OIL LEAK AT COMPRESSOR SIDE OF TURBOCHARGER

Possible cause

Remedy

Air cleaner element blocked.

Clean or replace air cleaner element.

Olieleiding turbo verstopt.

Check oil pipe. Replace if necessary.

Damaged turbocharger.

Replace turbocharger and identify the cause.

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4

DIAGNOSIS

XF engine inlet and exhaust system

95

XF series

3-4

FAULT: EXHAUST BACK PRESSURE TOO HIGH

Possible cause

Remedy

Incorrect butterfly valve setting.

Check the setting of the butterfly valve.

Butterfly valve incorrectly positioned.

Check whether the butterfly valve has been
positioned correctly.

Butterfly valve partially operated by residual
pressure in the operating cylinder.

Check operating cylinder.

No original exhaust silencer fitted.

Check exhaust silencer.

Exhaust pipe crushed or internally blocked by a
loose part.

Check exhaust system for blockage and/or
damage.

FAULT: INLET UNDERPRESSURE TOO HIGH

Possible cause

Remedy

Blocked air cleaner.

Check air cleaner element.

Obstruction in intake ducts at the rear of the cab.

Check the intake ducts.

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4

95

XF series

XF engine brake

DIAGNOSIS

4-1

4.  XF ENGINE BRAKE

4.1

FAULT-FINDING TABLE

FAULT: EXHAUST BRAKE DOES NOT ENGAGE

Possible cause

Remedy

Compressor delivers insufficient air pressure.

Check the operation of the compressor.

Defective engine stop valve.

Check engine stop valve.

Air leak in the air pipe from air drier to engine
stop valve.

Check air pipe.

Butterfly valve stuck in butterfly valve housing.

Check free movement of butterfly valve.

Defective engine stop operating cylinder.

Check operating cylinder.

Electrical fault.

Check electrical circuit.

FAULT: EXHAUST BRAKE REMAINS ENGAGED

Possible cause

Remedy

Defective engine stop valve.

Check engine stop valve.

Defective engine stop operating cylinder.

Check operating cylinder.

Butterfly valve stuck in butterfly valve housing.

Check free movement of butterfly valve.

Electrical fault.

Check electrical circuit.

FAULT: DEB CANNOT BE SWITCHED ON

Possible cause

Remedy

Electrical fault.

Check electrical circuit.

Engine oil pressure too low.

Check engine oil pressure.

1

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