Coil wiring question

Electrical issues
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JohnnyBadBrains
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Coil wiring question

#1

Post by JohnnyBadBrains » Fri Dec 17, 2010 1:47 am

So I'm down to this on my '56 Panhead. after the frame broke forward of upper motor mount, total disassembly, labeling and tagging and photographing everything I could think of, welding the frame, sandblasting, powdercoating, replacing most wiring etc..., I "think" I may have mis labeled my positive and negative coil wires. It is the cylinder style, spark plug wires up top, with + and - wiring ro ignitionand Volt regulator between them. I do not want to start her up after all these months, and dollars if I stand to screw something up over two wires. It has been converted to 12v, running Bosch regulator and would like to know if the positive post from coil goes to ignition or regulator. I could not find this in the knowledge base that's why I'm asking. AS always, I appreciate any help offered from my life line here :) :D

Johnny



FlatHeadSix
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Re: Coil wiring question

#2

Post by FlatHeadSix » Fri Dec 17, 2010 2:27 am

badbrains,
we had a discussion about this last year, here's a link to the thread:
viewtopic.php?f=5&t=5721&hilit=coil+polarity

mike

JohnnyBadBrains
Posts: 43
Joined: Sat Sep 15, 2007 8:12 pm
Bikes: 1956 FLH Panhead
1938 UL Flathead
1968 FL Shovel (Basket case)
2007 HD Street Bob
Location: Phoenix, Arizona
Has thanked: 4 times

Re: Coil wiring question

#3

Post by JohnnyBadBrains » Fri Dec 17, 2010 4:58 pm

HI FlatHead Six, appreciate the daigram, and especially the MG Auto club article, very helpful. If I could just clarify one thing in regards to the Clymer diagram being 'reversed' it is this- are the positive and negative indiactors drawn on that diagram correct, regardless of coil orinetation? If so, then my assumption that the negative coil post does wire up to the circuit breaker would be correct.

Thanks :)

FlatHeadSix
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Re: Coil wiring question

#4

Post by FlatHeadSix » Fri Dec 17, 2010 5:49 pm

yes, the (+) and (-) connections are correctly marked. Connect the power lead from the ignition switch to the (+), the wire from the circuit breaker to the (-).

Another "but"; it would not take much time or effort to try it both ways and see if it makes a difference in the appearance of the spark for YOUR equipment. There is a big difference in the appearance and behavior of spark jumping the gap in open air as opposed to in the cylinder under compression, but it is REALLY hard to see under actual operating conditions :lol: , so the only visual comparison you can do is with the plugs out. Try it, tell us what you see.

The bottom line is that it will work either way, and won't hurt the coil or any of the other stuff, but it might make a little difference in performance if the plug polarity is working in the direction that the MG Club article suggests.

good luck!, hope she runs great!

mike

JohnnyBadBrains
Posts: 43
Joined: Sat Sep 15, 2007 8:12 pm
Bikes: 1956 FLH Panhead
1938 UL Flathead
1968 FL Shovel (Basket case)
2007 HD Street Bob
Location: Phoenix, Arizona
Has thanked: 4 times

Re: Coil wiring question

#5

Post by JohnnyBadBrains » Sat Dec 18, 2010 1:13 am

yeah, yeah! I was thinking of doing that 'spark checking thing' thanks to the MG Auto article and the string you sent me the link for earlier. I will let you know what I come up with this weekend. Again, many thanks!

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