Mate asked me to look at his Mazda 3 as it was making "a loud ticking type noise"

Turns out the auxilary belt tensioner wheel has broken into bits (Known problem on these engines)

Has anybody done one of these ?

I've got the tensioner off (hoping to source just the wheel) but is there a secret in releiving the tensioner when fitting the auxilary belt again ?
Cos its under alot of internal spring pressure

Can releive the tensioner in the bench vice but can't think how i'll do it when fitted to the car
unless there's a special tool for this

Unless of course it should never be this tight in the first place ?


Any help appreciated

On many cars these things have a hex on them that allows you to hold the tension off against the spring and you then insert a pin into a hole in the body to lock it in the off position.

Thanks for the reply
But sadly no hex on this one
There is a very small 'flat' area on one part of it and i'm thinking there may well be a special tool
to make it easier
The spring tension is way too much at present imho and i'm thinking with a new assembly it will be
easier to releive the tension and fit the belt (original one fitted at present and 9 yrs old)

These things have Plastic pulleys and they shatter
Luckily my mate was at home and didn't overheat the engine as there are stories on the web of folk
lunching engines due to not stopping straight away

Ahhhh cracked it

You use the centre locating bolt for the pulley
Its left hand thread and you lock it and turn the unit against the spring pressure

Some days you can't see the wood for the trees : )

Now to see if we can just source the pulley...

[Edited on 3/3/12 by perksy]

Just for the benefit of the search function in case anybody else get one of these to do

Fitted the new tensioner today which came with the new a Steel (instead of plastic) tensioner wheel
This was a Gates one and cost £37

All nice and quiet again in the Mazda engine bay