Coil test

[GLEN DEUTSCH]

Having a devil of a time with the spark on a Johnson 9R69. I have tried everything. New condensers, new points (cleaned) , fixed the wobble, new plug wires, checked the kill switch, set timing with multimeter changed coils, wiggled everything for a loose connection. Some of the coils I am using are from other motors and look like new. Two of them are new. The primary and secondaries are intact. Secondaries measure 3.5 ohmes.. I have tried several different coils and switched them around to see if the spark follows any particular coil. Sometimes I get spark on top cylinder: sometimes both: sometimes neither. All without changing anything. I heated the coils with a hair drier and that seemed to help. Is there another test I can do on the coils? Seems unlikely that all six of my coils are faulty and yet test out OK. I have a new set of coils ordered from CDI. Hate to throw the other coils away, if they are OK.

[frankr]

How wide a spark are you trying to get? Will it spark a narrower gap? I sort of doubt it is the coils.

[outbdnut2]

On rare occasion I get a funky brand new condenser. When you heated the coils, the condensers probably got heated too and could be thermally intermittent.. I’d try swapping in some known good ones. It’s unlikely both new condensers are bad, but it’s something to try. You didn’t mention new spark plugs, but probably have replaced those too.
Dave

[Tubs]

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A "Boathouse Repair" is one that done without having tools or the skills to do it properly.

• This reply was modified 4 years, 7 months ago by Tubs.

[crosbyman]

secondaries at 3.5 ohms…:-( . 3.5 K ohms maybe if not someting is weird

Joining AOMCI has priviledges 🙂

[Mumbles]

Have you got the point cam in correctly with ‘TOP’ on it facing up?

[fleetwin]

OK, so your spark issues are resolved, correct??

[GLEN DEUTSCH]

Thanks all. I now have a few more things to try

[GLEN DEUTSCH]

Found out something new by accident going through old “ask a member”. The arms of the cheap Chinese piece of crap coils are not macined well at all. If you put them in a coil setting ring, you can see daylight between the center laminations and the ring. I measured about a dozen coils and found seven of them off by as much as 0.01. I ground the arms with my bench grinder to get them to fit properly. Also lapped the flywheel to the crank to reduce any chance of wobble. Put my “turtle” in the tank and it now runs. Need to wait until spring to see how it goes on the lake. Hope I am not too political when I say it tells you something about the values of a culture that will let such junk out the door. I keep looking for western made anything.

[fleetwin]

I hear ya buddy, we sat back and let our country be “sold out”, now we are paying the price is so many ways…

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