yamaha 2005 25hp 2 stroke - will not idle

[lilhuna]

It shuts off at low idle. Just want to adjust idle a little higher but cant seem to fiqure out how. Otherwise it runs great.

Thanks

 

[99yam40]

Re: yamaha 2005 25hp 2 stroke - will not idle

Idle on a properly adjusted motor, idle only changes when some thing is broke or has a problem.
Just raising the idle adjustment will not fix it.
Find out what the problem is and fix it, more than likely it is the carbs that need attention

 

[25yam10jon]

Re: yamaha 2005 25hp 2 stroke - will not idle

99yam40 - in most situations you are generally correct... just not in all as you definitively stated.

lilhuna - how many hours on engine? are you at elevation or nearer to sea level? have you moved to elevation? does your primer bulb go soft? does fuel filter bowl stay full? can you advance your throttle slightly and idle then? does fuel filter bowl stay full then? if you can idle your engine by slightly advancing throttle and you have a hand held tachometer, will it hold at 700-800rpm? i live at 7100 ft el and have had 2 outboards NEW out of box. 2004 johnson 9.9 4stroke and jut started breaking in a brand new 2009 yamaha 25 esh 2 stroke.
-Johnson - stalled at idle (FACTORY SETTINGS = properly adjusted motor). Slighly adjusted mechanical idle linkage screw and have never had to do anything to the motor since except plugs, engine and gear oil ( have about 700 hrs on engine).
-Yamaha - stalls at idle (FACTORY SETTING = properly adjusted motor). Have not yet figured out which is the idle adjust screw on the linkage. When I do I will post it. Just raising the idle MAY fix the problem. If you make any adjustments on any linkage screws mark the screw and mounting fixture with paint pen and count your turns so it can be returned if not the issue. Write it down as well so you don't forget!!!!!

 

[25yam10jon]

Re: yamaha 2005 25hp 2 stroke - will not idle

lilhuna - if it's just a low idle problem because of environmental/minor adjustment conditions i've found the adjustment screw to bump the idle.
*the adjustment screw is on the right side of the bottom carb (side of the engine with the fuel line - not the tiller side).
*the screw is a vertical phillips screw that pushes/pulls a linkage rod between both carbs. if you adjust this one screw it adjusts both throttle plates inside the carbs.
*you cannot see these plates as they are inside the carb - we are NOT talking about the choke plates.
*there is another small, horizontal screw in the middle of the linkage rod that that lengthens or shortens the rod - do not touch this screw.
*looking down at the screw ---- clockwise will increase idle ---- counterclockwise will decrease idle.

I turned mine 1/2 turn clockwise to bump my idle - idles flawlessly - shifts flawlessly - runs flawlessly. if you increase the idle too much the engine will almost certainly shift directly from F to R and R to F and won't go into neutral. make the adjustment with the engine in gear (F).

hope this is all you need and that there are no other problems like 99yam40 pointed out... could be a very real possibility. happy boating... keep us posted