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40hp 1962 Johnson coil check

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cws68

Member
Had some problems with boat running on one cylinder but able to make it back to dock. Speed was jumping up and down. Well i did need to change plug wires connections and points plus condensers.

Now took readings from primary side of coils and both read 0.00 Secondary side both read 8.6

Are these coils shot? secondary seems correct BUT I see primary should read between 0.2 and 0.4 i'm told by what i've been reading

ALL readings done on 200k ohm setting as directed

Thoughts???
 
Upper crankshaft seal replaced ?----Air gap on coils set correctly.-------Oiler wick in place to lube rubbing blocks ?-------Plug boots new ?-------Condensers tested / replaced ?----Coils are cheap so I replace them ( have them on hand ) so little cost to me.----Points set using a meter or feeler gauges ?
 
yes to everything EXCEPT crankshaft seal. Points set with gauge. Tested coils removed and got those readings so i figure primary of coils have shorted out. Will order new coils
Thank you
 
Just thought i'd reply to finding the problem. Upon pulling flywheel back off I had tightened down the 3 bolts for pulley wheel for belt. This caught coils and shorted them out. New coils again BUT just lightly snug down the 3 bolts and motor running great.

Thanks again
 
I did not think the pulley for the belt was bolted on from factory.----Or did you mean for the starter ratchet piece.----If those 3 bolts are too long it will damage the coils.----Picture of the belt pulley ?
 
cws68 said:
Had some problems with boat running on one cylinder but able to make it back to dock. Speed was jumping up and down. Well i did need to change plug wires connections and points plus condensers.

Now took readings from primary side of coils and both read 0.00 Secondary side both read 8.6

Are these coils shot? secondary seems correct BUT I see primary should read between 0.2 and 0.4 i'm told by what i've been reading

ALL readings done on 200k ohm setting as directed

Thoughts???
Click to expand...

Is 200K the lowest available on your meter? I would not expect an accurate reading in the 1-Ohm range at such a high setting.
 
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