Stihl 025C

[Jeff]

Hoping someone can help me out. I've got a Stihl 025C. It's about 20 to 25 years old. I can get it to run at high RPM but when I back it down to about half throttle it dies. I can never get it to run slow enough to have the chain stop. Bought it new, never loaned it out and always used 50:1 mix. Any ideas?

Thanks in advance,
Jeff

 

[Bob Hedgecutter]

Odds are pretty good, if a saw wont tune or hold tune- it usually has an air leak.
Take the muffler off and look at the piston through the exhaust port- is it scored up?
Pressure and vacuum test would be my first port of call.