Is a cracked upper dowel port fixable on the big 20B iron?

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Old 03-21-11, 05:32 PM
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PR Is a cracked upper dowel port fixable on the big 20B iron?

A local machine shop got a request from a 20B owner to try and fix the upper oil / dowel pin port on the big iron. It broke at the 500whp level in a TurboII chassis, not that it matters. So, has anyone successfully fixed this?
Old 03-25-11, 05:41 PM
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I have done one on a 13b. It worked but I also back the power down a little just in case. I was making around 400whp when it broke. We had a problem with gas station selling 89 octane as 91. Got a check for 80$!!!!! hahah dam oil companies.
Old 03-26-11, 10:36 PM
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Originally Posted by 13bdarren
I have done one on a 13b. It worked but I also back the power down a little just in case. I was making around 400whp when it broke. We had a problem with gas station selling 89 octane as 91. Got a check for 80$!!!!! hahah dam oil companies.


I know your in Canada but, what gas station?
Old 03-27-11, 01:23 PM
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the shop owner's idea is to weld it and build it up then machine it back, sounds like it can work but I was wondering if it's been done before with good results
Old 03-27-11, 04:38 PM
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I couldn't tell you how it would compare in strength vs. a stock cast dowel land but it's not magic, it's just an alignment hole. How well it works will depend on how accurate he can machine it to original standards. I imagine it would create a weakness, but if it was me I would definitely try it vs. buying a new one! holy hell those things are expensive.
Old 03-27-11, 04:53 PM
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you can repair it, but it break again, in the same spot..
Old 03-28-11, 10:03 AM
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Yes there is a way to fix it with out breaking.

Contact us at 248-250-0967

Chip U
Old 04-02-11, 03:21 PM
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I got mine welded and then machined back to limits again.
Putted the engine back together and unes it for one season in my racecar, had no problems with it after the repair.

So its just to go ahead and weld it..
Old 04-13-11, 12:35 AM
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IT can be successfully welded no problem. I am a CWI and a weld engineer/designer for a big fabrication shop and we weld things like this all the time. I have in fact welded the very spot on my 20b when i broke it.
Old 04-13-11, 01:18 AM
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Try to find a shop that use TWS (Thermal Wire Spraying) and talk to them.
Old 04-19-11, 12:01 AM
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Why not dowel or oversize stud the motor and do the oil bypass by plugging the oil gallery and run the oil from the oil sandwich to the front iron? I know it is hard to describe by it is the best way and you don't have to worry about losing oil when the dowel area cracks again.
Old 05-13-11, 07:10 AM
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PR

If you are in PR call RG Machine shop may be he can help you 787-525-5621

jorge
Old 05-17-11, 04:30 PM
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PR

thanks to all for the ideas, it's not my motor it was at a friend's machine shop. They ended up doing this:

Originally Posted by jamespond24
Why not dowel or oversize stud the motor and do the oil bypass by plugging the oil gallery and run the oil from the oil sandwich to the front iron? I know it is hard to describe by it is the best way and you don't have to worry about losing oil when the dowel area cracks again.

and the engine is back together and running again. last dyno (when it broke) was around 500whp at 15psi. I don't know the turbo or any other details about it...
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