S23 NOISE' GEARBOX / IN A SPECIFIC GEAR - Alfa - 156 - eLearn

3233159 - S23 NOISE' GEARBOX / IN A SPECIFIC GEAR

With the engine running, a noise is heard (whilsting inside the gearbox) when a specific gear is engagedThis noise decreases or disappears on changing gear.

1	CHECK SYNCHRONIZER RINGS	All OK	Problems met	Operation
		Results of the tests
	Overhaul the gearbox (see OVERHAULING GEARBOX Assembly 2110B).In particular, check the synchronizer rings for the gear involved: they should not show signs of wear on the inner surfaces	Continue to Step 2	Seals worn	Replace the synchronizers
2	CHECK GEARS	All OK	Problems met	Operation
	Overhaul the gearbox (see OVERHAULING GEARBOX Assembly 2110B).In particular, check the teeth of the gear concerned: they should not be worn or show signs of seizing	Continue to Step 3	Gears worn	Replace the gears involved
3	REDUCTION TORQUE CHECK	All OK	Problems met	Operation
	Check the crown wheel and pinion reduction gear (see OVERHAULING GEARBOX Assembly 2110D) In particular: it should not be worn or damaged there should not be excessive clearance	Continue to Step 4	Reduction gear damaged	Restore the clearance or, if necessary, replace the reduction gear
4	CHECK CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis	Fault persists	Search for the fault starting from another symptom'