I have a 1998 25 Yamaha 4 stroke that has been wonderful. I had not used it for around 5 months. Last time I took it out, It started and ran perfect, But after I got to my spot, I went to idle down to put it into neutral and it wouldn't idle all the way down. I looked at the linkage and it was bottomed out where it was suppose to go. I killed the engine in gear then switched it to neutral, then started it back up and it idled fine for 10 seconds, then it sped up on it's on without me touching anything. I fooled with it for a while then decided to come back to the boat launch. I did look to make sure everything was greased and workning smooth. It will start and run perfectly smooth with plenty of power, Just when I start it after 10 or 12 seconds it will idle up by it's self. And I checked to make sure it wasn't vibrating and the throttle was moving. I also held the throttle all the way down to idle and it still idled up by it's self. I can start it and hurry and put it in gear and it will speed up in gear. What should I look at? I keep fresh fuel in it and I have a good fuel filter with a water trap. And also keep stabilizer in it when I don't use it for a while.
Last edited: