VERY erratic idle: 1984 90* V4 90HP Evinrude

[Larry Engelbrecht]

It sounds like some of the cylinders are hitting erratically. Has great power but the idling rpm jumps all over the place. It stutters, then instantly goes up to 1500 rpm, back and forth. The idle wasn't this bad before I rebuilt the carbs. Everything is clean, new floats are set to specs. No missing hoises. Any suggestions where to start? Thank you.

 

[boobie]

Re: VERY erratic idle: 1984 90* V4 90HP Evinrude

Have you done a sync & link on it ??

 

[emdsapmgr]

Re: VERY erratic idle: 1984 90* V4 90HP Evinrude

Agree. Check your sync and link. If one of the pairs of carb butterflys does not close fully, you can get erratic idle rpm's. Pull off the airbox cover to make sure the carb butterflys are completely closed on both carbs at idle.