Rough idle or no idle on a 998

[Simplespeed]

If you are experiencing a rough or no idle on a 998 there are three air screws that have a tiny O rings on them that will cause this condition when the O ring degrades from heat cycles during normal operation . As these motors age this problem has been showing up on some sleds… I believe these screws only control air during idle..

 

[jonlafon1]

Pictures?

 

[Turboflash]

X2. Where are they? And, doesn't ISC do it's job to control idle?

 

[Simplespeed]

I don’t have the parts manual where Iam at right now but someone that does can find them as I can assure you they are there and yamaha has a kit to rebuild them that includes O ring… I posted this information cause I don’t remember anyone referring to this condition that causes this problem. If too much air is allowed in the motor, it will not idle at all on its own or idle really rough all due to a bad tiny O ring…