Pulley clatter when steering with aircon on

Hi, can anyone help?

2000 Multipla JTD, almost 70,000 miles.

When the aircon is on, turn the steering with a load on it (e.g. full lock or tyre pressing against the kerb), get a very very loud clattering sound from somewhere in the timing belt area. My mechanic checked and suspected worn clutch on the aircon unit, so I called an aircon specialist.

He checked the aircon and said it's working fine and demonstrated that you can hear the same clattering, but much quieter, when steering with the aircon off. He said it could be wear on another pulley the belt goes round.

My mechanic fitted a new fan belt and timing belt kit a couple of months ago. Anyone suggest what might be wrong?

Thanks!

FWIW most cars make a noise/clatter/whine/hissing/knocking when the steering is on full lock or against a solid object like a kerb. The steering is being put under maximum stress and the whole drive train and steering pump internals are are full chat. Most of the oil output is going through the system relief valve and that too will make unusual noises. Plus you will heat the oil very quickly which will thin even thinner than it is already and it will be less efficient. Cure - don't do it ! Always avoid full lock if at all possible. Eventually something like the pump or valve will give way.

cheers
mish

missionary,

Thanks for the info. I do try not to use full lock etc. Trouble is this noise occurs when steering and driving normally, and can be heard above the engine/wind noise/kids whining etc. In other words it's loud, and the clattering sounds like a cross between something plastic broken and the noise you get when you put cardboard into your spinning bicycle spokes.

Try this thread: http://www.fiatforum.com/multipla/14...ngine-bay.html

OK HMM then I take it all back and apologise having now read the other thread as suggested.

So you seem to have what I am trying to prevent. I have a very gentle squeak coming from the crank pulley, and thankfully its not anything like your noise. As you can see by my other thread today, I am tackling the job myself. Though I am driving 100 miles today so it might nto be so quiet when I get back home !

cheers
mish

Hello,

I have just sorted this very problem on my wife's 2001 Multipla JTD.

In a nutshell, the problem is with the crankshaft pulley which has a rubber damper built into it. Basically there are two pieces of metal held together by the rubber damper. In my case the rubber had perished (see picture) which allowed the two metal pieces to make contact creating the clatter. This was particularly noticeable when either the air con is switched on or when steering when there is increased load on the belt.

I have replaced the crank pulley (about £70.00) and the engine now sounds very sweet indeed.

One final note: This is the first time I have ever come across a crank pulley that is other than solid metal. My own Marea JTD130 has a solid metal crank pulley as did my old Tempra TD and every other car I have owned. Does any one know what the rubber damper is for?

Hope this is of help.

Ian

Pleased you have cracked it now. Its just one of those features that we all have to learn with a new car - I am learning fast too!

Although I have not yet removed mine to replace - as you can see by my other posting ! They are not uncommon. Its known as a harmonic or dynamic balancer; or in other words helps dampen vibrations. My greater experience is on the Toyota LandCruiser, on which vehicle they last about 150,000 miles. Unfortunately we have to lower expectations for Fiat ! HTH

cheers
mish

Thanks all, my crankshaft pulley has similar perishing, must be that then!