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early/late crankcase question

Moderators: Curt!, Pa

Post Fri Jan 10, 2014 9:16 pm

Posts: 86
even'n folks. working on another ULH bobber, i was wondering if early and late cases can be mated up? not concerned with blind bushings, baffles, but is there any major reason say a 37 and a 46 would not be workable together as a pair. have an early set with an old repair on one half and i have a good later case half i would rather use

Post Fri Jan 10, 2014 11:28 pm

Posts: 386
They mate just fine. The later cases don't have baffles along with the through races. Otherwise pretty much the same and will bolt right up.

Post Sat Jan 11, 2014 2:31 pm

Posts: 86
colony machine co offers two different case bolt kits, basically early and late U's. was wondering what was different with these kits? thanks robbie, your info is always trusted as sage advice. mark

Post Sat Jan 11, 2014 6:47 pm

Posts: 607
Location: Menomonie, Wisconsin, USA
Early motors did not use aligning studs and later motors 1941 and up did. Jerry

Post Sun Jan 12, 2014 9:08 am

Posts: 1644
Location: Interlaken, NY USA

Here's a set of
"37" cases on ebay, mismatched, but what caught my eye is the catch basin in place around the rear exhaust cam gear. Didn't think that 37's had this feature, but the belly numbers look o.k. Any thoughts?
also looks like someone reamed the right side case to remove the flange. ... 1423.l2649


Post Sun Jan 12, 2014 10:16 am
don User avatar

Posts: 571
Location: Spokane WA USA
My 37 matched set, with VIn in 7000 range does not have the raised casting taller than an installed scavenger drive gear.
But, The production numbers are in the 6700 range.
The #'s on the Ebay example are 7500.

Another difference is '37,'38,'39 Did not have a relief for Screen between Scavenger tower and case.

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