1967 Johnson 40HP - NO SPARK

copnap

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Sep 27, 2007
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Purchased a bigger boat and engine for duck hunting and I am ready to sink it. Engine is a 1967 Johnson 40 HP electric start with electric shift and generator (Model #RKL29E). It started the day I bought the boat but then would not turn off with the key and I had to choke it out.

Two days later I started it at home and it ran for two-three seconds and stalled out. Now there is no spark and I am lost. Season is getting close and I think im shooting from shore this year.
 

JB

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45,907
Re: 1967 Johnson 40HP - NO SPARK

The ignition in your engine is two magnetos, Copnap. The only things they have in common are the ignition key (which un-grounds the points when "ON") and the flywheel.

I suspect that the "ignition" switch is at fault here, particularly because it would not kill the engine before.
 

tmcalavy

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Aug 29, 2001
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Re: 1967 Johnson 40HP - NO SPARK

JB is correct, magneto ignition. Remove the top cowl and recoil, if there is one. There may be a port/plate on the flywheel that you can move to see down into the mag. Check the coils. If they are cracked, they need to be replaced. Also check condition of the points and the point gap. I'm betting the switch as JB mentioned. Can't tell you how to run the rabbit on that one cause I only use pull start outboards. Once you get it running you'll be able to run the ducks down.
 

copnap

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Re: 1967 Johnson 40HP - NO SPARK

I have been told that I can just disconnect the two magnetos wires from the ignition switch and this should allow spark, just will have no way to stop the engine. Tried it and still no spark. Have pulled the fly wheel and cleaned the points and gapped them at .020. All looks real clean and intact. There are two black wires that I see coming from the two points and one runs all the way back to the ignition switch (black wire to magneto) and the other is not connected to anything. Where should this second black wire be contected?


I have more questions for someone that is familiar with this engine and set up. Direct e-mail is copnap@yahoo.com if anyone has the time to help out. Appreciate everything.
 

F_R

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Re: 1967 Johnson 40HP - NO SPARK

Second black wire goes to the center terminal of the vacuum cut-out switch on side of the motor. Another black wire goes from that same center terminal, to the other "M" terminal on the ignition switch. The switch electrically connects the two black wires together to stop the motor.

But that has nothing to do with why it has no spark now (since it wasn't even hooked up).

Is the flywheel key sheared by any chance??
 

copnap

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Sep 27, 2007
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Re: 1967 Johnson 40HP - NO SPARK

Key was sheared off and replaced today. Still not getting anywhere though. I am not to familiar with the vacuum cut-off switch, when does this come into play with the electric system?
 
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