I have an quadrunner that wont idle ive tried cleaning air filters and the mixture screw .when i turn up the mixture screw higher it wont revv back down. we have to give the atv half throttle to start it and it wont stay running. it will run on idle for probably 3-10 seconds then stall. What Do i Do?

 

Will it idle with the choke on? Will it idle if you turn up the idle speed?

 

will it not idle at all? or just a few seconds. most 2 strokes dont idle as well as four strokes. early 90's cr 250's didnt idle more than 10 seconds really unless everything was perfectly adjusted. i would guess if its not your idle screw or air screw,probably jetting,wrong fuel/oil mix,could be a few things,just go down the list

 

this is a four stroke engine. When i use the choke it does nothing if i pull it all the way there is no diffrence on how the motor is run . And when i turn up the idle mixture screw it revs to high then it wont come to an idle.

is there a screw just for the idle not the idle mixture screw.
and where is the air screw

 

The idle adjustment is on the shifter side. The Idle adjustment sticks out, is a flat head, and should have a spring on it. You may have a clogged starting circuit in the carb.

 

When i turn up the idle mixture screw it revs to high when i give it throttle so i have to turn it back down.
There must be some kind of adjustment or something that will higher your idle speed but not the revvs when you give it gas. Anyone know

 

There isn't. There is the pilot screw, and the idle screw. The Pilot screw is supposed to be 2 5/8's turns out. Something is likely clogging the starter circuit. You should pull the carb and give it a soaking in staring fluid, then blow out the jets, and passages.

 

where is the pilot screw

 

Just below the idle adustment.

 

alb
In this picture ... the idle speed adjust is #9. It goes into a ramp on the slide, which moves the slide higher for a faster speed.
#28 is the pilot air screw, this adjusts the mixture, during idle. After you adjust the pilot screw, turn the rpms down with the speed screw.