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Cal-look/High Performance => Cal-look => Topic started by: Brandon Sinclair on March 15, 2009, 09:09:11 am



Title: Mahle main bearings partially covering oil holes
Post by: Brandon Sinclair on March 15, 2009, 09:09:11 am
This is my first experience using Mahle main bearings.  All my past experiences have been with KS bearings, but I have been unable to locate any for this engine.  Anyway for the split center main and the thrust bearing the oil grooves are on the outside of the bearing towards the case.  The oil holes in the case are exactly in the middle of the saddle but the oil groove in the bearing is not direclty in the middle and the oil holes are 1/2 way covered up.  What is the correct fix for this-either: 1. modify the bearing (maybe cut a half moon shape so the entire oil hole will be exposed), 2. oval out the hole in the case saddle so the oil gets to the entire oil groove in the bearing, 3. try some new bearings (if so which kind or where can I find some German KS).

Thanks


Title: Re: Mahle main bearings partially covering oil holes
Post by: 181 on March 15, 2009, 10:25:27 am
I had a very simmilar problem with KS bearings on my AS41 mag case.

(http://lh5.ggpht.com/_nKjezkastzY/SZH9eS-OfaI/AAAAAAAAAGQ/ne30vzN6z8U/s640/ksbearing.jpg)

I modified holes in the case with Dremel tool, bearing stayed untouched. In your case, if the holes mismatch for one half, I would modify the backside of the bearing (teardrop the hole a bit) and the hole in the case too.


Title: Re: Mahle main bearings partially covering oil holes
Post by: Brandon Sinclair on March 15, 2009, 21:22:38 pm
I wish mine were that close.  Anyone know where I can find a main bearing set for KS .060" case, standard on the crank and thrust?

I found this photo of a Mahle bearing being end milled for the oil port-I guess I can do the same with my dremel if I have no other option.

http://images.thesamba.com/vw/gallery/pix/265641.jpg


Title: Re: Mahle main bearings partially covering oil holes
Post by: Jim Ratto on March 16, 2009, 16:56:55 pm
Brandon, are you running this .060 case in the same motor you are worried about rod side clearances?  :o


Title: Re: Mahle main bearings partially covering oil holes
Post by: Brandon Sinclair on March 16, 2009, 19:35:53 pm
Yeah, what was I thinking?  Oh well too late now.  It is only a 1776 anyways so I will see how it turns out shortly.