fast idle

[jatco]

i have a v6 225 johnson i changed the old gas and now have a fast idle. all adjustments that i can see are maxed out . how do i slow this engine down?? any help someone, please

 

[Franki]

Re: fast idle

is it a carb model? are you saying that the idle screw is all the way out?<br /><br />If its not one of the usual things, I'd go looking for an air leak.. it could be sucking air in somewhere which can cause your problem.<br /><br />rgds<br /><br />Frank

 

[jatco]

Re: fast idle

franki it is 89 johnson with carbs. there is no more adjustment. there was a lot of oil in the gas and it was very oldbut the engine idled okay. after i change the gas it began to race. whats up

 

[ICEMAN]

Re: fast idle

HI, Here's a couple items to check. That motor has six carburetors in it's design. Two of them are on one base and two are on their own base. There are a few adjustments with this set-up. There is a connector to connect one side bank to the other, then between the middle and lower carburetor there is a connector. Take the front cover off and look at the carburetor plates and see if they are all closed. If all three on one side are open, you need to adjust the top connector, if a bottom carb is open, or the top two, you need to adjust the connector between the mid and bottom carb. If all the carburetors are open, you need to adjust the screw on the throttle arm reducing the lenght of it. There should also be an adjustment screw on the link between the armature plate under the flywheel and the throttle arm. If that is out of adjustment, the engine can race up also.

 

[johnk@olg.com]

Re: fast idle

Hello madmoney - Are you seeing this fast idle with the boat hauled out? If so, try it in the water and see if it slows down. I have an '89 175 Evinrude that would idle real fast - not less than 1400 to 1500 RPM some times. Sometimes it would slow down to about 1200 to 1300 but that was it. This was while it was running on a hose in my driveway and fully warmed up. This afternoon I launched it for a water test and it ran slower, about 950 RPM in neutral, 800 in gear. Which is a little fast maybe but definitely useable. I'm thinking (and hoping)that my fast idle was just due the lack of back pressure the motor sees on the exhaust when she's hauled out as compared to in the water. Now I have to admit that I don't recall this much difference in the past and it does not seem related to your gas change but its something to consider.

 

[jwhite]

Re: fast idle

If adjusting the carbs or linkage doesnt work then look at the pack. If yours has a square pack on the top of the left head (standing behind the boat) then its probably carbs or linkage, but if it has the big pack inbetween the heads then it might be the idle circuit in the pack which would mean you need a new pack.<br /><br />whitesmarine@tds.net