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197?4? Johnson 40hp electrical issues

Hey guys I'm trying to help my brother out here, he has a 40hp Johnson don't know the exact year but believe it to be 70's about 74, model#40e74s it hasn't ran in years and the guy he got it from lost the ignition key, so we hooked up fuel to it and we noticed the 2 smaller red wires that hook up to the starter solenoid where the batt wire goes were broken off, so we just ran a quick temp wire from the battery Pos to those wires and twisted them together. Then he took all the wires off the back of ignition and just hooked them all together except the white one, left that one aside because it ran the starter. Everything seemed fine so we cranked on it a few times and noticed that the electric choke wasn't working so we ran the switch wire to the ignition also, then he tried cranking again and as soon as we hooked the battery up those red wires started smoking, so we disconnected the choke wire and it still did it, we did notice one coil seemed to be warmer then the other and was cracked so we took one off an 85hp I had sitting around and put that on temporarily thinking the coil was fried, still smoked. As soon as we put power to those red wires they smoke. It seems that as soon as we either unplug the coil connectors at the engine, or unhook them up where the ignition was the red wires stop smoking, I'm wondering is there a wire we have hooked up at the ignition end that should be getting 12v+ and is grounding something out? Any wiring diagrams would help alot.
 
Stop------The battery and 12 volts are not used to make spark for the plugs.-----I think you may have burned up some expensive parts.-----Yes , I have a 1974 model like that , will be taken apart with the 11 year old grandson.----Have new pistons / rings on hand if it needs them.
 
I doubt the 85hp coil will work on that motor. But whether it will or not, as racerone said, connecting 12V to them will burn them up. You for sure need a manual or diagram or something to go by other than guesswork.
 
Ok thanks, yes I Hate going by guess work and almost never do because I hate to mess things up, I will continue to try and find what each wire does. How does this motor get "shutdown"? I know some motors give 12v+ to the coils or Magento or something in the spark system to energize them and kick them on so turning the ignition off cuts the power which in turn cuts the spark. Or are these motors more like lawn-mower engines where when you turn the ignition off it grounds the coils to cut spark? Maybe that's the issue is he has the grounding "off" wire hooked up with the 12v+ causing it to ground out if that's how this system works? If anybody could help clarify which of the 2 systems the motor uses that would help alot.
 
The ignition is powered by the spinning flywheel !!----The battery and 12 volts do not make spark at all.-----The ignition simply grounds out to stop the motor !
 
The ignition is powered by the spinning flywheel !!----The battery and 12 volts do not make spark at all.-----The ignition simply grounds out to stop the motor !

Ok thanks, that's what I was wondering and what I thought so it's a typical style ignition system. So I think that's where he's going wrong is I think he's supplying 12v+ to the grounding wires.
 
Ok so bad news... I took a look myself and yes he had both blue wires connected to 12v+, so I disconnected them and instantly the red wires stopped smoking, so I then left them hang there while I cranked on it to check for spark... Nothing.. So I then tried unplugging both safety switches (one under the flywheel and neutral safety) both times still no spark... So I tried taking the blue wires off what looks like the vacuum solenoid? Switch? Figuring if it's a faulty switch grounding them out if I undo their grounding source it would give me spark. Still nothing. So to try and figure out what he likely fried I took one of his coils back off and put one off my 85 on there, both are 2 wires only difference seemed to be 2 bolt mounting vs 3 bolt, and his used a plug style connector vs my 85 used a ring type connector to a stud, so I jammed the ring connector into his plug temporarily, still no spark... So I'm guessing he fried something under the flywheel, I did take the flywheel off and everything looks clean under there and the points move freely. Is there anything else I should check? Also what likely fried if something did.
 
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