View Full Version : Stihl FS110 4mix Cutting out High RPM'S

08-25-2009, 10:56 AM
Can anyone give me some advice on this?
I have a FS110 with 25-2 trimmer head. It runs excellent and starts easily until under a load at high RPM's. It will rev fine until I attack really tall grass. it almost seems like an electrical problem as it cuts right off. I can keep it running if I close the throttle-it goes to idle. Running clean fresh gas, filter looks good and unit is about 2 years old. Never had the Spark Arrestor out but not sure if this would do it. Any help is appreciated.

08-26-2009, 04:06 AM
Coil or carburetor, sorry I'm not sure which one right now and I'm also assuming
a lot of stuff, like you already put a new air filter and a new spark plug in it.

08-26-2009, 02:43 PM
Sounds like carb needs adjusting. Sounds like maybe going lean. My fs90 don same thing back in spring, service guy adjusted carb and ready to go.

Two Seasons
08-26-2009, 08:27 PM
Sounds like a combo problem.
1.) Take the screen out and clean it with gas.
2.) Mix up a new batch of 92 octane with Stihl HP Ultra oil
3.) Check the valve gap for 0.015"---if you can't do it, dealer will for about $40.

08-26-2009, 11:43 PM
Not likely the coil, usually if those coils fail they will start up but not accelerate at all. Most likely a fuel delivery issue. Just out of curiousity have you replaced the plug yet. not saying it could be the problem but I did have an issue with this before