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Determine main bearing size

Hi,

I have a question about ordering main bearings. I am replacing the crankshaft in my case with a new, counterweighted crank. I don't have the old bearings. I have the old crank. A shop put on the #3 bearing for me but said I'd need to bring my case in to get the right size #1 bearing, which I never ended up having time to do, and I've since moved.

So, I need to know how to determine what size bearings I need to buy using only any information I can get from the old crank, the new crank, the case, and a vernier caliper.

The crank is a BugPack counterweighted crankshaft and the case is stock. The crank has two yellow lines and two white lines painted on one of the counterweights and a few numbers stamped or perhaps cast in various places, as well as the VW Logo. The case has a set of three two-digit numbers on each half of the flywheel housing well away from the center, and on the left half right outside the flywheel seal is engraved " 0 2 0 " with nothing on the right half. Please assist me in determining what bearing thrust size and bore size I need to get- or tell me how to determine this. Everything I've been able to find so far is very uninformative and contains a small bit of information from people who seem to know more.

What would be nice would be a list of all the real-life measurements corresponding to the .010's, 20's, 30's, etc. that I see on the parts websites.

Thanks,

Jon Harvey

Reply to
jdharvey
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I've measured the size of the case and new crank, and my measurements are as follows. I'm not sure that I'm using the right terminology but this is what I seem to have gathered from the other posts and the internet as a whole. What I'm actually measuring is therefore described parenthetically after the term I use:

Thrust size (width of the case that has to be encompassed by the flange on the #1 bearing):

22.00 mm +/- .05mm Case size (inner diameter of the hole in the case for the #1 bearing): 65.50 mm +/- .05mm Crank size (outer diameter of the bearing surface [measured very, very carefully!] for the #1 bearing on the crank): 54.50 mm +/- .05mm

But I'm still at a loss as to what the standard sizes are, and therefore, what I need to order. Please let me know asap, as I have about 2 weeks to get this engine together before I'm moving to a place with no garage!

Thanks,

Jon Harvey

Reply to
jdharvey

Standard OD of main bearing = 2.559"

0.020" over = 2.579" (~65.5mm) 0.040" over = 2.599"

Standard thrust for flywheel side bearing flange = 0.100" The next oversize = 0.140"

Standard thrust = 0.865" (~22mm)

The opposite flange is always = 0.100"

A standard crank main journal = 2.164"

0.020" under = 2.144" (~54.5mm)

It appears to me that your case has a stock thrust width but has been bored 0.020" over. I also appears to me that you "new" crank is used that has been ground 0.020" under. I got my figures from the CB Performance Catalog. - Robert

Reply to
Robert

Thanks for your help! It seems that the appropriate size to order would then be .020" case / .020" crank / standard thrust. I was thinking of ordering from GEX, any input on that?

Thanks again, this has been a source of frustration for me and it's good to get it out of the way!

Jon

Reply to
jdharvey

GEX does not rate high on customer satisfaction.... just bearings, maybe, but do you really want to support a company that has a history of poor workmanship and even worse customer service? go to

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and search the forums for "GEX"... allow some time and read up...

Reply to
Joey Tribiani

help! It seems that the appropriate size to order

I would think the bearing you had pressed on the crank would have the size on it.

I always buy full bearing sets, who ever you get them from ask for Maile.

Mario Vintage Werks resto

Reply to
Kafertoys

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