M20 Pilot Bearing

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ianarthur
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Post Tue Nov 11, 2014 5:28 pm

Hi all
I’m current replacing the engine in a friend’s 90 325 saloon, the engine going in is from an Auto so requires pilot bearing into the end of the Crank. I must be going blind as I cannot find it on RealOEM (I accept it must be there somewhere), and calls to my local partners in crime are being less than helpful.

Does anyone know of a supplier for a Pilot bearing?
HairyScreech
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Post Tue Nov 11, 2014 5:32 pm

Standard bearing for these.
IIRC its a 12ix32ox10w bearing. I have on the bench in the garage if you want me to have a quick check.

What gearbox are you using though as it does make a difference?

Edit - oh and its here: http://bmwfans.info/parts-catalog/E30-T ... eel/#pos_8
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
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Brianmoooore
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Post Tue Nov 11, 2014 6:41 pm

Note that the only part you need is the bearing. All the other parts associated with it have long since been deleted.
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ianarthur
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Post Wed Nov 12, 2014 8:44 am

It's just a standard 325 SE, unsure which box it is but it will be the one it left the factory with
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Brianmoooore
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Post Wed Nov 12, 2014 9:59 am

The bearing above is the correct one, but it's always good practice to check the centre bore of the bearing against the pilot shaft ogf the gearbox.
Later BMW gearboxes used a slightly bigger pilot shaft, which requires a corresponding change in the bearing, if they are used with E30 engines, and similarly, if a later manual engine is used with a E30 gearbox, the bearing fitted to the engine might have a bore which is too big.
HairyScreech
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Post Wed Nov 12, 2014 1:11 pm

Yesïaaas above, they went from a 12mm pilot to a 15mm pilot.
The change was around the e36 start so it is possible to find E30s with 15mm inner diameter bearings in, come across it on a 318is.

Not sure if it began life that way though.

Good news is regardless of the inner bearing diameter the outer and width is still the same.

Also new bearings seem to help a lot with input shaft/lay shaft rattle.
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&