1989 Evinrude 120hp

" Engine runs fine at idle and

" Engine runs fine at idle and at low RPM, but when I open the throttle, it shakes like crazy.

Any idea? "

" Randy,

My guess would be

" Randy,

My guess would be that the power pack is going, but you would need a peak reading voltmeter to analyze your ignition properly.

Tony "

"Randy.... With so little to g

"Randy.... With so little to go on, that problem could be anything from a s/plug breaking down to a piston getting ready to blow. Take a compression check, then check the spark (with the s/plugs out). The spark should jump a 7/16 gap on all cylinders. Get back to us with the compression readings and the results of the spark test. Has the engine been sitting for any length of time; a couple months or more? If so, a carburetor high speed jet may be clogged/fouled, allowing enough fuel mixture for a smooth running engine at idle or intermediate speed only. Give us a little history on this engine such as when was the last time it ran normal, has it sat for some time since then, etc?

Joe "

Joe & Tony:
Thanks for g

Joe & Tony:
Thanks for getting back to me.
Joe:
Engine was running fine the same day a couple of hours earlier...occurred all of a sudden with no warning.

Am bringing boat in to a pro.

Randy