rumble from auxiliary belt area

[harrykins]

Hi I am getting a rumble from the front of my 2002 superb. If i ease the pressure off the auxiliary tensioner it reduces. A garage says it might be the clutch on the alternator and it will cost around £200 tochang including tensioner ,has anyone had this problem and is it easy to change the clutch

[rotodiesel]

The clutch pulley is very easy to change if you have the tools. The rotor holding tool differs according to whether a Bosch or a Valeo alternator is fitted. £200 is a ripoff. Shop around for the part and get an independent to fit it for a fair price - or buy the tool and do it yourself - you would be well in profit.

Depending on which engine your car has, the fan may need to be moved forwards to access the lower alternator fixing bolt. The fan shaft is held from the rear with an M8 hex bolt. Hold the fan drum assembly with the belt tensioner (19 AF spanner) and slip a folded piece of glass paper between the drum and the drive belt to release. The glass paper stops it slipping - works like a charm.

rotodiesel.

Edited 9 June, 2012 by rotodiesel

[harrykins]

The clutch pulley is very easy to change if you have the tools. The rotor holding tool differs according to whether a Bosch or a Valeo alternator is fitted. £200 is a ripoff. Shop around for the part and get an independent to fit it for a fair price - or buy the tool and do it yourself - you would be well in profit.

Depending on which engine your car has, the fan may need to be moved forwards to access the lower alternator fixing bolt. The fan shaft is held from the rear with an M8 hex bolt. Hold the fan drum assembly with the belt tensioner (19 AF spanner) and slip a folded piece of glass paper between the drum and the drive belt to release. The glass paper stops it slipping - works like a charm.

rotodiesel.

cheers for that i have the 1.9 tdi 130 engine .The £200 included changing the tensioner pulley as well as the clutch which I believe means entails stripping part of the front down to be able to get at it,dont know if thats correct or not. How can I check the alternator clutch Edited 9 June, 2012 by harrykins

[rotodiesel]

A simple check for the alternator clutch, with the engine off, can be made by inserting a small screwdriver into the front ventilation slots of the alternator. Taking very great care not to damage the stator windings, engage a blade of the internal alternator fan and check that it turns fairly easily clockwise as you look at it, but locks solid anti-clock.

A better check is to remove the aux drive belt and spin the alternator clockwise by hand, holding onto the pulley. As you hold the pulley after an initial twist, the alternator rotor should continue to freewheel if the sprag clutch in the pulley is operating correctly. Any pulley with > 85k miles use is potentially suspect.

The belt tensioner is fairly expensive and the front needs to be pulled to fit it. Unless it is obviously defective, change the alternator pulley first.

rotodiesel.

[dohertyjj]

<p>Before you go spending money on the altenator pully check the free running cooling fan I like you had a growl in that area it appeared a few weeks ago but for a long time I had a whirring noise everyone knew it was my car coming sounded like a jet landing very softly changed the altenator pulley then the tensioner (good job I was able to return these bits) they made no difference. Then a few weeks ago it turned into a growl so by holding the cooling fan stationary with the car idling the noise stopped it turned out to be the bearings on the bracket that the bolt holding on the pulley goes through so check this out</p>

<p>P.S don't know if these bearings can be replaced I just replaced the bracket with one from a vw passat</p>