1948 WL 45 Ignigion Switch / Coil Problems

[Tedster100]

I've got a '48 WL 45" that runs great but keeps blowing coils. I got it partially restored and finished it but it has a 5 position switch in lieu of the 7 position. I searched and have the PDF of the 5 wire switch from Perry Ruiter's site (thanks!) but wondered if anyone could offer any advice or suggestions before I dig-in. It has been converted to 12v and has a Cycle Electric generator. When the bike is running the generator light is lit but the system is charging (my first clue something may not be wired correctly). The coil does get hot while running and eventually at about 45-60 minutes it starts to cut-out. Once cooled it runs fine again until it heats up. I picked up a new 12 volt coil but want to make sure I get everything straight before running again. Aside from double checking the wiring according to the 5 position switch does anyone have any suggestions of anything else that could be wrong or need checked along with the wiring? With new paint and a fresh engine re-build I want to be able to ride without worring about getting stranded by another blown coil.

Thanks!

[Sargehere]

Sounds egg-zackly like it would act if you had wired up a 6 volt coil in a 12 volt circuit, 2me. Sorry I can't be of more help.

If it's a repro coil, did you attach to (+) lead from the switch to the back terminal, as the coil is mounted on the bike? That's critical, too. The primary is wound backwards on the Taiwan repop coils (and they're all the same, from the same source, regardless of vendor).

This ground has already been covered pretty well, I think. Here's some reading for you, from many contributors to the subject:

http://www.caimag.com/forum/showthre...ss-repro-coils

http://www.caimag.com/forum/showthre...uot-coils-Fail

I just gave up, and hose-clamped a late-model Harley-Davidson OEM coil to my frame tube at one point, and never had another coil problem! Others have found other solutions, like rebuilt OEM 6-volt coils, and emptying stock coil covers and hiding a little aftermarket coil inside, thing like that. But I have had aftermarket coils as bought from Tedd's V-Twin last as long as three years, and and short as ten minutes before failing. Good luck!

[Tedster100]

Thanks for the info, that should help in getting it wired correctly. Funny thing was that the first thing I replaced after buying the bike was the coil & it was 12 volt, I replaced it & with a later model off of a early Panhead I believe. It still bolted up but was the round coil. Once it failed I replaced with the old style square coil & it lasted for a while & then totally quit. I'm thinking it's related to the ignition switch & coil wiring and I've got a new coil sitting on the bench, just don't want to fry it without trying to solve the problem.