[mybre4kf4st]

Hi, i'm having trouble with my Stihl MS271, i can start it up with the choke half open but it revs like mad, then when i give it some throttle it stalls unless i really rev it up, but even the it stalls sometime.
I've cleaned the carb out, flushed the fuel lines through, changed the spark, cleaned the air and fuel filter, checked the compression.
Any help greatly appreciated

 

[StrokedTater]

Sounds like an air leak. I would check around the intake really well. Could also be a crank seal.

 

[jaguar]

replace the crank seals

 

[Bad Ass Honda 250r]

If im not mistaken those are stihls newer stratified scavenging 2 stroke engine. does the carburetor have two butterflys in it? when you pull the filter off?