Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

[hsdtech]

Just bought a boat with '89 evinrude. Installed new water pump. Was running ok, but since the motor was sitting up for probably a year or so I figured the carbs needed going through. My brother cleaned the carbs, put the linkage, etc. back like it was. Now when we crank the motor it revs VERY high. I have to turn the motor off it revs so high.
One thing to NOTE, he said when he first took carbs apart that the FLOAT needle was NOT hooked to the pin on the float. So he hooked the float needle to the pin. I don't see why this would make the motor idle real fast. Sound to me like an AIR LEAK. But where???
We are supposed to go fishing tomorrow, advice needed ASAP. Thanks.

 

[adoseth]

Re: Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

make sure your throttle butterflies are actually closing and make sure your throttle arm that advances the timing is also returning all the way back

 

[nwcove]

Re: Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

ditto to adoseth.......sounds like there could be a linkage issue, or a forgotten return spring. look there first. but a vacuum leak where the carbs bolt to the intake could also cause a lean " high idle" condition. just look for the obvious stuff first.

 

[Tim Frank]

Re: Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

First thing I'd check for a "too fast idle" is the idle speed adjusting screw....

 

[hsdtech]

Re: Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

make sure your throttle butterflies are actually closing and make sure your throttle arm that advances the timing is also returning all the way back

First off, thanks to everyone for the replies. Yes I checked the butterflies, the throttle arm is returning, where it meets the little stopper connected to the linkage.

 

[hsdtech]

Re: Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

First thing I'd check for a "too fast idle" is the idle speed adjusting screw....

We checked the idle screws several, several times.

 

[hsdtech]

Re: Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

ditto to adoseth.......sounds like there could be a linkage issue, or a forgotten return spring. look there first. but a vacuum leak where the carbs bolt to the intake could also cause a lean " high idle" condition. just look for the obvious stuff first.

We checked, looked, checked some more. I'm also thinking its a vacuum leak.

 

[hsdtech]

Re: Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

make sure your throttle butterflies are actually closing and make sure your throttle arm that advances the timing is also returning all the way back

The butterflies are closing, but leave a little gap. This is necessary for idle, correct?

 

[AlTn]

Re: Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

not certain of that year's setup, but the ones I've fooled with the throttle plate is completely closed at idle

 

[AlTn]

Re: Need Help ASAP - '89 40hp rude - Cleaned Carbs Now Very HIGH Idle

no gap at idle