Surges when accelerating 1985 60hp

[Stumpalump]

1985 johnson 2cyl 60. When accelerating it is not smooth and linear but increases in power in little bursts. Starts and runs WOT perfect. Carbs and ignition are new. Only thing I can think of is the timing is advancing in increments instead of smooth. I oiled the linkage that I can see and it seems to move OK. Am I missing something or could something under the flywheel possibly be sticking? I really have to watch the throttle because if I push it enough to get on plane it feels like somebody is pumping the throttle. Once it settles down and I throttle back it runs perfect. Any ideas? Thanks.

 

[racerone]

Re: Surges when accelerating 1985 60hp

Put a timing light on it and see if there is an ignition fault that comes and goes.---------Observe the flashing light.------Look for a plug wire that might be shorted and arcing to the metal bracket on the cowl.-------Test for that would be to run without the cowling.

 

[Stumpalump]

Re: Surges when accelerating 1985 60hp

It's got a new CDI, plugs and coils but it does run like it's some sort of ignition problem. The fuel lines and carbs are all sorted out as well.

 

[racerone]

Re: Surges when accelerating 1985 60hp

You need to do some testing.

 

[boobie]

Re: Surges when accelerating 1985 60hp

Do a cylinder drop test on it to see if you can nail it down to any one cylinder.

 

[Stumpalump]

Re: Surges when accelerating 1985 60hp

That's a good idea I'll try it. Thanks