1976 9.9HP Johnson

[Dale in MD]

Hello,

been dealing with a spark issue. Points good (0.020"), condensors good (go to "Open"), primary coil good (2 ohms), external coils good, new plugs - lost #1 cylinder in short order afterward.

Coils are about 1.3 / 1.5 ohm on primaries and 12.9k / 13.5k on secondaries.

I believe my problem is my coil wires from the coils to the plugs. I could feel the one wire zapping me while running when I grabbed it with a thin pair of leather gloves on, so I know its insulation is bad. For troubleshooting purposes, I did 3 layers of electrical tape on it from end to end. The motor ran well for a good for 5 minutes while running hard. As soon as I idled down, cylinder died again. It cuts in/out instantaneously, so I believe its spark, not fuel issue.

I checked the plug wire resistance from the coil to the cap - best I see is 200k - 300k ohm range. Hard to even get a consistant reading. The wires are the older type with actual "wire stands" vs. newer caron type wires.

What is a good resistance reading for these wires? (I would think next to nothing)

Can you buy just the wires or do you have to get coil and all??

Thanks,

Dale

 

[wilde1j]

Re: 1976 9.9HP Johnson

Parts list doesn't show the spark plug wires as separate parts. Looks like you need to get the coils/leads.

 

[Rick.]

Re: 1976 9.9HP Johnson

I'm 90% sure on that old of motor the plug wires are changeable. The preferred wires are steel core not carbon core for your motor. Any OMC dealer will have a roll and cut the lengths you need from it. Best of luck. Rick.

 

[Waco]

Re: 1976 9.9HP Johnson

i am having the same issue with 1976 15hp. did you find a solution? any information would be greatly appreciated!