are 4 strokes supposed to shake when idle?

[dannieboiz]

It's been a year since I needed to use my 2002 15hp 4 stroke. I had an idling issue with the motor recently where it won't stay on. I took the carb apart and cleaned everything out and it fixed the problem. At the same time I installed new plugs. Going to do an oil change tomorrow.

I hardly use this motor so I can't recall if it was ever super smooth but comparing to my old 98 Honda 4 stroke 9.9 this motor is louder and seem to run rougher. When I say rougher, I mean it tend to shake more and does the same thing when I rev it up.

I didn't have a spark plug gapper so I used something else to measure it to the exact gap as the current old plug. I don't know if that could cause the shaky idle.

 

[oldman570]

Re: are 4 strokes supposed to shake when idle?

If you have replaced the plugs you might try putting one of the old ones back in the motor and use it to see if one of the new plugs is causing it to shake bad. Being that the new plugs gap was set without a gage they could be the trouble or one of them is bad right out of the box. JMO
Oldman570