M20 timing belts

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Cloggy Saint
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Post Thu Nov 29, 2012 5:06 pm

I see the realoem lists 2 different numbers for M20 belts, but what's the difference?
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Brianmoooore
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Post Thu Nov 29, 2012 8:20 pm

IIRC, rounded teeth and square edged teeth.
Cloggy Saint
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Post Sat Dec 01, 2012 11:29 pm

Cheers. Is this an item that's best bought from the dealer or would a motor factor give a good quality copy?
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e30topless
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Post Sat Dec 01, 2012 11:32 pm

I once had this at a motor factors, I was suprised to learn there were 2 types, one was longer than the other IIRC

buy one from the dealer not that expensive and if you quote your Vin you should get the correct belt,
Cloggy Saint
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Post Sun Dec 02, 2012 12:01 am

Cheers, rough price guide, with tensioner?
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capri_rob
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Post Sun Dec 02, 2012 7:20 am

Contitech manufacture the belts for BMW - which are available from ECP.
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pacerpete
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Post Sun Dec 02, 2012 12:42 pm

The early square tooth belt was only used on E12s and E21s. If you use an E30 vin you should have no problem getting the right parts. Go ECP , same parts at a third of the dealer price.
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Post Sun Dec 02, 2012 1:12 pm

im sure i also saw somewhere that one type has one more ”atooth”a than the other,
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Andyboy
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Post Sun Dec 02, 2012 5:54 pm

Square tooth belts were used on early M20 (M60) engines, 2.0 and 2.3 with carb/K Jet. Replaced in late '81 by round tooth belts so no E30 will have a square tooth belt.
Belt and tensioner well over £100 at BMW, Contitech belt kit £45.
HairyScreech
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Post Sun Dec 02, 2012 6:29 pm

Andyboy wrote:Square tooth belts were used on early M20 (M60) engines, 2.0 and 2.3 with carb/K Jet. Replaced in late '81 by round tooth belts so no E30 will have a square tooth belt.
Belt and tensioner well over £100 at BMW, Contitech belt kit £45.
:cry: So my e21 turdmeister will be square tooth then, will have to swap to some spare e30 pulleys so I only need to keep one belt on the shelf for both cars.

First i had heard of this as well!

Would that mean the square tooth is only on the older style stamped pulleys?
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

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http://www.e30zone.net/modules.php?name ... =viewtopic&
Andyboy
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Post Sun Dec 02, 2012 6:40 pm

Fitting later pulleys is a major ballache. The crank pulley doesn't fit so you either machine it down or fit a later front oil seal housing as well.

Top Tip: just use the right belt.
pacerpete
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Post Sun Dec 02, 2012 11:41 pm

I have a new boxed early belt for sale. No E21 will ever be allowed on the premises so I will not use it :)