1986 Johnson 120 HP Outboard Intermittent No Spark on All cylinders

[mkantar]

I have a 1986 120 HP Johnson that intermittently stops firing on all cylinders. The engine will keep running while this happens, resulting in the engine jerking back and forth as all 4 cylinders fire and then stop firing. It also stalls a lot when this is not happening. I believe that if it was a power pack, then this would only happen on one bank, and not both? I'm sort of unsure how to proceed from here. From what I've read it seems likely that this is the stator or timer base, but I wanted to get from input. Any help or suggestions would be greatly appreciated.

 

[boobie]

Re: 1986 Johnson 120 HP Outboard Intermittent No Spark on All cylinders

Go to cdielectronics.com. They have good ignition system trouble shooting procedures.

 

[mkantar]

Re: 1986 Johnson 120 HP Outboard Intermittent No Spark on All cylinders

All the info I find on there is either one cylinder with no fire, one bank with no fire, or no spark on all cylinders (not intermittent). I can't seem to find anything about all four cylinders firing and then not firing and then firing again.

 

[GCarlover]

Re: 1986 Johnson 120 HP Outboard Intermittent No Spark on All cylinders

Your's is the same as my 87 140. No electronic fast idle and no S.L.O.W. to run on two cylinders when overheating. When my power pack went out it wouldn't idle and the timing light was jumping all over the place. Only one power pack on these outboards. I think the older ones have two.

 

[mkantar]

Re: 1986 Johnson 120 HP Outboard Intermittent No Spark on All cylinders

Your's is the same as my 87 140. No electronic fast idle and no S.L.O.W. to run on two cylinders when overheating. When my power pack went out it wouldn't idle and the timing light was jumping all over the place. Only one power pack on these outboards. I think the older ones have two.

Thank you for pointing out that I only had one power pack. I had originally ruled out the power pack because I thought only one bank would stop firing and they couldn't both be broken at the same time lol. I replaced the power pack the other day and it hasn't happened since