adjusting the idle

[mickey117]

i have a 1985 90hp. evinrude.it seems to be idling a little high.when on a hose it idles at 1500 rpm.i read that it should be 750 to 850 rpm (on hose) to adjust the manual says to do it in the water with boat in gear. does anyone know of a way to adjust the idle on a hose?

 

[WillyBWright]

Re: adjusting the idle

Adjust for about 200 high on the hose. That'll get you in the ballpark. But in the water, warm, and in gear is the only correct method. Make sure all throttle butterflies are fully closed. Idle is adjusted via timing.

 

[mickey117]

Re: adjusting the idle

isn't it as simple as turning the idle screw down till the tach reads 200?

 

[mickey117]

Re: adjusting the idle

does adjusting the idle mean that i have to mess w/timing.

 

[shaggs69r]

Re: adjusting the idle

no i think they mean 200 rpm above recomended rpm if on hose

eg if in gear in water idle should be 850 rpm then go around 1050 if on a hose should be damn close
good luck!

 

[Dhadley]

Re: adjusting the idle

Once you do the sync-n-link the butterflies will be closed at idle. Turning the throttle arm stop screw out will allow for a lower idle. It's pulling the idle timing back. Do the sync-n-link adjustments with the throttle cable off. Then once the motor idles as it should, adjust the cable.

Start with a compression test, then sync-n-link. The motor will idle at 650-750 in the water, in gear if the motor is healthy.

 

[Joe Reeves]

Re: adjusting the idle

On that model, on a flushette (hose), with the water turned on full blast, the idle in neutral should be as follows:

20" shaft engine = 1000 rpm

25" shaft engine = 1200 rpm

In the water the back pressure will cause the idle rpm to drop to normal.