Technical Multipla cambelt change problem

[mercur1al]

My Multipla is currently with my local Fiat garage for a routine 60,000 service and cam belt replacement. During the latter, the garage managed to shear off the locking nut/washer thing (I don't know the correct name) that secures the lower pulley wheel. As a consequence the lower crankshaft now needs to be replaced as well - at an additional cost of ~£800!!

The garage initially expected me to pay the extra bill (just like that) but I've refused and said that the garage should cover it as they caused the damage. The garage is currently consulting head office as it doesn't seem able to make the decision itself.

What are your thoughts? Does this problem occur very often when replacing a cambelt on a Multipla or any other car? What's the most likely cause? Metal fatigue? Too much force? If it is a known problem shouldn't I have been forewarned about it?
Thanks in advance for any advice.

 

[andmc]

It is hard to say exactly what caused the failure without a proper investigation. Unfortunately there are a number of factors such as corrosion, previous tightening torque and joint condition all of which were out of your garage's control. The only way I can see the garage being liable is if they were careless in their actions.

The head office may offer to cover some of the costs out of goodwill, but in any case it would be worth taking professional advice to better understand your position before negotiating (I am not a lawyer)

There is a website on fastener failure called boltscience.com that gives some useful background info.

There may be some other options to consider besides replacement of the crankshaft: e.g. attempt removal of the broken screw (nothing to loose at this point). A replacement second hand engine would be less than £800.

Good luck

 

[mercur1al]

Thanks for the reply. Following my protestations, head office has apparently requested a "technical assessment" from the garage. I'm not sure what that entails, but I suppose it might give them some answers about possible corrosion etc that you mention.

You also mention "broken screw" but from what I was shown (and photographed) the faulty bit seems to be a little threaded washer thing that is welded on to the body of the engine through which the end of the crankshaft pokes. The locking nut for the pulley wheel then grips this threaded washer. Does that make sense?

 

[andmc]

This forum won't let me post URLs yet, but doing a google search on "multipla crank pulley" takes you to a picture of a failed pully, is this anything like what you were shown?

I'd be interested to see what the garage's report says. Would you be able to post some more info when you get it?

Thanks.

 

[mercur1al]

Yes, I'll give you an update from the garage report as soon as I hear anything. Thanks for your interest. In the meantime here is a photo of the offending threaded washer thing. As you can see it's sort of mottled in appearance, which may suggest some particular type of corrosion.