I have an FS45 that is about 10yrs old and haven't had any issues with it until this spring. This spring I added new gas mix (fresh gas and new Stihl mix per directions) and it ran fine the first use. The last (2nd) time I went to run it, whenever I gave it a lot of throttle (past 3/4) it tried to die, but letting off the throttle completely it also attempted to die. In the revving up condition is when it'd run, so I was blipping the throttle constantly until it got up to operating temp and then it worked fine with good throttle response. I went to use it again (3rd time) and now it won't even fire. Pull and pull and pull and no attempt to even fire, choke or no choke. I first pulled the spark plug and I can see spark when pulling the cord. Plug was wet from my start attempt. I pulled the in-tank fuel fillter and it looked perfectly clean, but also installed a new one. I pulled the carb and completely took it apart and cleaned good with carb cleaner and reassembled. The carb bulb primes fine, and I tested the prime function when I had it pulled off and it gave a good squeak. I then put a spoonful of gas into the cylinder to bypass any potential fuel delivery issues and still nothing. Air cleaner is new. I have air, fuel, and spark so the next thing I checked was compression and I got 105psi. I'm at a loss. Any ideas?
Can the ignition modules slowly go out, i.e. there is spark but has weak spark? I could see spark but it wasn't crazy bright. Does anyone have instructions on testing the coil? I hate throwing parts at something until I figure out the cause, especially a $50 coil on a $150 trimmer.
Can the ignition modules slowly go out, i.e. there is spark but has weak spark? I could see spark but it wasn't crazy bright. Does anyone have instructions on testing the coil? I hate throwing parts at something until I figure out the cause, especially a $50 coil on a $150 trimmer.