1976 Johnson 85HP 2 cylinders not firing question

cfish4448

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Oct 30, 2020
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I have an old family boat that I am trying to get running. The left side cylinders are not firing but the right side are. Inside the power pack the bottom row orange wires go to the left side, the side not firing, cylinders and the top row of orange wires goes to the right side cylinders. Whenever I move one of the orange wires down to the bottom row it fires. When I move one of the orange wires from the bottom to the top, it fires. But whenever the left side orange wires are on the bottom how they are supposed to be they wont fire. Does anyone have any idea of what is going on?
 

Jemstone80

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Oct 13, 2022
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1
I have an old family boat that I am trying to get running. The left side cylinders are not firing but the right side are. Inside the power pack the bottom row orange wires go to the left side, the side not firing, cylinders and the top row of orange wires goes to the right side cylinders. Whenever I move one of the orange wires down to the bottom row it fires. When I move one of the orange wires from the bottom to the top, it fires. But whenever the left side orange wires are on the bottom how they are supposed to be they wont fire. Does anyone have any idea of what is going on?
In 2014 I bought a 16' Glastron with a 85 hp Johnson on it. I believe they are both 1978 vintage, and for $700.00 for the boat motor and trailer with a forever license, I can't complain. The motor would start and run but it was obvious 1 side wasn't running right. I put on a new power pack on that side and for a couple of years it ran great. I use the boat EVERY Monday and Friday from ice out until Ice on and maybe once again in the middle of the week if I get a chance. I have replaced all 4 coils and new plug wires since then and the plug wires that come with the replacement coils leave a lot to be desired. You get a wire, 2 springs and two boots and have to assemble the plug wire yourself. I found that soldering the springs to the wire is the best way to do it. I would suggest you start with at least 1 new power pack on the side that won't fire and go from there. I think the orange wire your referring to is from the coil going to the power pack, be sure they are connected well to your coils and the power pack. You might want to think about replacing your coils or at least testing them to be sure they are firing by pulling a plug wire and see if the motor starts and runs the same when you pull each wire.
 

McGR

Senior Chief Petty Officer
Joined
Jun 19, 2004
Messages
667
Attached is an image of the power pack circuit, including internal componentry. Also see full wiring diagram: https://maxrules.com/graphics/omc/wiring/V4_1973.jpg

Sounds like it's either a sensor coil as one coil fires two cylinders or the power pack. Sensor coils should measure around 15-20Ω with an Ohmmeter.

I hope this helps.
pp.jpg
 
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