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TR2/3/3A C39 Lucas Generator

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Frank_D

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Hey folks; looking for some info on my C39 generator. I recently sent it out for re-build and it came back minus the bras nuts for the two posts. The C39 does not have Lucar connectors. Does anyone have any idea what the thread and nut sizes are, one larges and one small? I may have to source these and I suspect that they may not be easy to find.

Thanks for any advice........... Frank D................
 
Frank, check out you local Harley Shop, as I think they were Whitworth threads and Harley used them for many years. As info, put a star washer behind the nut.

Wayne
 
I believe the small stud is 3/16 BSF (32 tpi), the large one is 1/4 BSF (26 tpi). However, it's worth double-checking what you have, since it is at least possible the rebuilder changed them.

Make sure the insulators are in place. IIRC the small stud should have a phenolic sleeve that fits around the stud between it and the end cover, plus a phenolic washer between the inner nut and the end cover. No lockwasher on the inner nut, as that would tear up the phenolic washer. I seem to recall that the large stud should have two nuts as well, but just a washer under the inner nut, no sleeve required.
 
The stud back plate is beginning to be rare. They come up on EBay every month or so.
 
Thank you Wayne, Randall and John. Good advice all around. Randall, the small stud does have the phenolic sleeve that you describe. I am going to a pretty big Brit Car Flea Market on Sunday and I am now well equipped to solve my little problem. Most appreciated.

Frank D..........
 
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