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MG MGF Technical - cambelt tensioner

hi guys. im looking for guidance(links) with relation to changing the cam belt tensioner which seems to squeal on start up for about 1 min and then is quiet. any special tools required.
The car is a 96 f
thanks in advance. Tony


My F does the same squeal on start up, but as it seams to be only on cold or damp days I put it down to the fan belt!. you have me a little worried now :o(

I think sometimes i just look for probs for an excuse to play with my f.
the noise i hear is not like the squeal you get from a belt sliping but more a high pitch whirring noise from the belt area. my car is only a sunday car. if i use the car two days running i dont get the noise at all, only if i leave the car for a week i hear it

Cold damp squealy fan belt is quite common on many cars ...

but search the archive for 'cam belt tensioner' and there are a load of hits. Quite a few have caused fairly large repair bills when the eventually let go - often after a period of squealing at startup!!

General advice is get it checked before too late.

Mark, you have a workshop manual

Tony, you could have one (on CD) if you emailed your postal address to jponting AT globalnet DOT co DOT uk

I beleive that no special tools are shown as needed (other than a cam locker) but there are manual and automatic tensioners depending on age of car.

The following usefull comments thnx to Roger Parker (Posted 13 October 2001)

"Manual type belt tensioners are approx 25ukp plus vat. (manual type fit all VVC and 1.8i up to approx late 1998)

General advice following on from Carls comments to anyone whose belt whines after a change, or work involving slackening and retensioning of the belt.

Get it reset correctly ASAP the strain imposed on the belt, adjuster and water pump bearings will cause rapid wear that can easily lead to premature failure."


thanks John I will email you as suggested.tony

A squealing noise that goes away shortly after startup is most likely a slipping alternator belt.


I would agree with you normally, and hopefully this time as well, but the archive shows too many hits of a sqealy belt followed by cam belt tensioner failure.

Can't help with the technical side, but you do get a distinctive metallic oscillating squeel rather than a belt noise. My P reg 'F'(see hydragas sadness) having blessed me with the same problem. If you have the facilities and time it sound s like a job worth doing as the labour charge for mine was around the 250 area!!
S Callaway

Thanks JP.

Started it this morning but no noise, but will get it looked at just in case.

Frightening pix of tensioner failure here:

Noise could be due to incorrect cam belt tension - TimW is an expert at this - usually most audible at idle, and changes tone with engine speed - if that sounds familar to you Tony?
Rob Bell

very much so Rob.
no noise when hot though. is the normal rule about that you can turn the belt 90 degrees apply on the k series engine

The cam belt should be tighter than that Tony. Need to look up the tension required - unless someone else has that figure handy?

Yours should still have the manual tensioner - unless it's been replaced with the automatic one at some point?
Rob Bell

the tension is set automagicly using the spring which is part of the manual tensioner, but its is held by a bolt.
Will Munns

The symptoms seem more like an alternator belt and not the cam belt so a lot simpler.

Cam belt tensioner - The type of tensioner depends of the age of the car. Early cars had manual items with only a slotted slider, later ones had the built in self adjusting spring. You're almost right about the rule of thumb (twisting the belt through 90 degrees) but you have to make sure that the load is on the correct side of the belt when you do this test otherwise you can easily get it wrong.
tim woolcott

How far are you supposed to be able to push the cam belt between the inlet and exhaust cams Tim? A couple of cm wasn't it?
Rob Bell

>between the inlet and exhaust cams Tim?


like no cm!

ITYM _Crank_ and exhaust cam - ie the longest strech.
Will Munns

This thread was discussed between 27/11/2004 and 29/11/2004

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