89' Johnson 120 no firing

paul118

Cadet
Joined
May 29, 2011
Messages
7
Hello all, I have a 120 Johnson thats not firing on two cylinders ( left top and bottom). I've done a compression test and it's 125 on all and also a carb rebuild. I also ran it off a seperate fuel tank into the VRO and replaced all plug wires. It won't plane off and is only running and 1/3 under load and is sputtering. I have someone else driving it when I pump the fuel bulb and its the same result. It's when I did a spark test yesterday when I found the no spark issue. What would be causing the no spark?
 

clanton

Rear Admiral
Joined
Jul 9, 2001
Messages
4,876
Re: 89' Johnson 120 no firing

Power pack, would be a good start. What kind of plug wires, metal core?
 

fshrgy99

Seaman
Joined
Jun 4, 2010
Messages
69
Re: 89' Johnson 120 no firing

my 89 140 starting working after I pulled the coils and cleaned the contact surfaces. Went from 8 MPH to 37 MPH (would idle fine). I think spark was breaking down under load.
 
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