Aux drive belt tensioner pulley

Eddie Zedder

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Hi fellow Zedders.

Has anybody changed the auxilliary drive belt tensioner pulley on a M52tu engine?

Mine has developed a squeeky bearing. The tensioner mechanism is ok so I am looking to just change the pulley. Is this easy to do, will I need special tooling or would it be better to replace the whole unit?

Thanks,

Bryan.
 

mwpe

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Mine is an M54 but I think they are much the same, I changed the whole uniy last year but on examining it afterwards realised that it is quite simple to replace the pulley. ECP stock them.
 

Grumps

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@t-thanked mine BrIan when he did all the water system change for me. Can never remember if mine is a tu or not but it certainly didn't take him long.
 

Eddie Zedder

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Mine is an M54 but I think they are much the same, I changed the whole uniy last year but on examining it afterwards realised that it is quite simple to replace the pulley. ECP stock them.
Thank you. I think there is a hex bolt concealed behind the pulley cover, but I'm not sure if a bearing puller is required to remove the pulley.
 

Eddie Zedder

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@t-thanked mine BrIan when he did all the water system change for me. Can never remember if mine is a tu or not but it certainly didn't take him long.
Thanks Dave. I'm sure @t-tony will be along sooner or later.
The tu is double vanos, I think pre 1999 are single vanos if that helps.
 

t-tony

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If you remove the plastic cap you can access the Allen screw that holds the bearing onto the arm. It should pull off easily.

Tony.
 

Brian4

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Hi @Eddie Zedder mine is an M54 as well but when changing @Grumpy he had the new tensioner.

As tony says flip off the cover on the centre of the pulley and the bolt is exposed and once out the pulley lifts off.

If yours looks like the one on the right I couldn't find a replacement pulley so got a new tensioner on left. It pick up on holes in the crankcase and all the fixings come with it.

Might also be worth changing the idler pulley as well.

Tensioner.jpg

Tensioner2.jpg
 

Eddie Zedder

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Hi @Eddie Zedder mine is an M54 as well but when changing @Grumpy he had the new tensioner.

As tony says flip off the cover on the centre of the pulley and the bolt is exposed and once out the pulley lifts off.

If yours looks like the one on the right I couldn't find a replacement pulley so got a new tensioner on left. It pick up on holes in the crankcase and all the fixings come with it.

Might also be worth changing the idler pulley as well.

View attachment 51377
View attachment 51378
Thanks Brian.

Mine is the right hand one, so it looks like I shall have to buy the complete unit.

Thanks again,

Bryan.
 

t-tony

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Thanks Brian.

Mine is the right hand one, so it looks like I shall have to buy the complete unit.

Thanks again,

Bryan.
One more tip before you do it Bryan, the new type of tensioner uses a threaded hole which the old one did not. A good idea to run a thread tap down this hole before fitting the tensioner just to make sure the thread is clear all the way to the bottom of the hole, if it isn't the new bolt may not tighten fully.

Tony.
 

Eddie Zedder

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One more tip before you do it Bryan, the new type of tensioner uses a threaded hole which the old one did not. A good idea to run a thread tap down this hole before fitting the tensioner just to make sure the thread is clear all the way to the bottom of the hole, if it isn't the new bolt may not tighten fully.

Tony.
Great tip there Tony. Thanks.
 
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