B engine rebuild questions

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   Starting to collect info and parts for a winter project of rebuilding the motor in a '49 B.  A couple questions:  
It looks like 3 7/16" bore is the normal sleeve/piston kits available rather than 3 3/8".  Any reason for this other than increasing displacement?  Is there some other reason why nobody offers the original bore?
Also wondering if its worth the trouble to fit modern lip seals on the crank rather than the felt and cork.  Sleeves or filling the oil grooves with JB weld are the two methods I've read about.  This will be a working tractor, not a display, so I'm not going to sweat a drop or two weeping from the seals, but I'm not sure what to expect from new cork and felt.

Incidentally, this was a motor that was completely (top and bottom end) filled with water from years of sitting in the rain.  The sleeves are pretty trashed with rust on top, but amazingly the bottom end looks pretty good.  Torn down except for the crank/cam, so hopeful I don't find any major issues.

thanks!

Edited by Luke114 - 24 Oct 2019 at 10:23am

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Luke114 Members Profile Send Private Message Find Members Posts Add to Buddy List Bronze Level Joined: 27 Aug 2019 Location: Washington Points: 109	Post Options Post Reply Quote Luke114 Report Post Thanks(0) Quote Reply Topic: B engine rebuild questions Posted: 24 Oct 2019 at 10:08am
	Starting to collect info and parts for a winter project of rebuilding the motor in a '49 B. A couple questions: It looks like 3 7/16" bore is the normal sleeve/piston kits available rather than 3 3/8". Any reason for this other than increasing displacement? Is there some other reason why nobody offers the original bore? Also wondering if its worth the trouble to fit modern lip seals on the crank rather than the felt and cork. Sleeves or filling the oil grooves with JB weld are the two methods I've read about. This will be a working tractor, not a display, so I'm not going to sweat a drop or two weeping from the seals, but I'm not sure what to expect from new cork and felt. Incidentally, this was a motor that was completely (top and bottom end) filled with water from years of sitting in the rain. The sleeves are pretty trashed with rust on top, but amazingly the bottom end looks pretty good. Torn down except for the crank/cam, so hopeful I don't find any major issues. thanks! Edited by Luke114 - 24 Oct 2019 at 10:23am

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Sugarmaker Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 12 Jul 2013 Location: Albion PA Points: 8436	Post Options Post Reply Quote Sugarmaker Report Post Thanks(0) Quote Reply Posted: 24 Oct 2019 at 11:59am
	Luke, Welcome! I would make sure it has not froze and cracked the block as a next thing to check. I have used speedi-sleeves to cover the crank grooves. Sounds like a good project. Not sure on the overbore, seems to be pretty standard now. Regards, Chris
	D17 1958 (NFE), WD45 1954 (NFE), WD 1952 (NFE), WD 1950 (WFE), Allis F-40 forklift, Allis CA, Allis D14, Ford Jubilee, Many IH Cub Cadets, 32 Ford Dump, 65 Comet.

WF owner Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 12 May 2013 Location: Bombay NY Points: 4898	Post Options Post Reply Quote WF owner Report Post Thanks(0) Quote Reply Posted: 24 Oct 2019 at 3:39pm
	If it had that much rain water in it, I would have the head checked for cracks, too. No sense in spending a lot of time and work if it has cracks..

Gerald J. Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 12 Sep 2009 Location: Hamilton Co, IA Points: 5636	Post Options Post Reply Quote Gerald J. Report Post Thanks(0) Quote Reply Posted: 24 Oct 2019 at 5:38pm
	The shop manual should help with details: http://geraldj.networkiowa.com/Trees/Allis-Chalmers-G-B-C-CA-Service.pdf Gerald J.