How to determine and eliminate what is squeaking in the drive belt area ?

[Bodgedbuild]

AC pulleys have an electo-magnetic clutch but I've not come across an alternator with any type of setup other than a fixed pulley.

It is extremely common these days, almost all diesel engines have an an alternator clutch pulley. It was never required when V belts were used but now with flat belts and the tendency for very long belts, it was a simple remedy to reduce the amount belts thrash about.

 

[Bodgedbuild]

Not doubting you, but why would an alternator have or need a clutch, the engine only rotates one way, the alternator can only be driven one way?

 

[HERTS P&D]

Take it to Kwik Fit!



Or try some lube .......................on the belt, I'm sure you have some!

Andy

 

[dontbelieveawordofit]

thought the alternator clutch was to stabilise voltage and eliminate spikes on start up on newer vehicles with delicate electronics.

 

[Bodgedbuild]

thought the alternator clutch was to stabilise voltage and eliminate spikes on start up on newer vehicles with delicate electronics.

If you ever get the chance to, grab hold of the pulley on one, it rotates quite easy in one direction without actually driving the armature and is locked with the armature in the other. A failed one is normally locked both ways (to the armature which still turns) and the obvious visible sign is the belt thrashing around either on tickover or a certain rev ranges.

 

[dontbelieveawordofit]

If you ever get the chance to, grab hold of the pulley on one, it rotates quite easy in one direction without actually driving the armature and is locked with the armature in the other. A failed one is normally locked both ways (to the armature which still turns) and the obvious visible sign is the belt thrashing around either on tickover or a certain rev ranges.

i’ve had my hands on a few