Stihl 021 woes

[Bob in Oakboro]

My Stihl 021 has developed problems. Sometimes it does not want to start. Sometimes it is fine. At other times it will be running fine and then just slows down and dies. Most of the time when it has warmed up and you have been running it and let it drop back to idle, it will die. Sometimes it will start right back up and other times it will not start back up and you must quit work for a while until it cools off. So far we have replaced the spark plug, air filter, and a fuel line. Fuel filter looks fine. Put fresh gas mixture in it, but no change in starting problems. This saw is fairly new, I still am using the original blade that came with the saw, but I am starting to think that I will have to replace it. I bought a Stihl because of their good reputation, but i am getting frustrated. So far dealer has charged me 50 dollars but I see more money going out of my wallet tomorrow. Any ideas as to what is wrong???

Thanks

Bob

 

[Anonymous-0]

I'd say maybe you got a dirty carb(inside not outside)

 

[El Toro]

Is there fire to the sparkplug when it warms up and quits? Hal

 

[Ken Crisman]

Check the fuel filter inside the gas tank . If it shuts down while running maybe its vapor locking .Dump gas out of thE TANK INTO A CLEAN JAR ; check for dirt because not everyone is careful about making sure their saw is cleaned off before refills .How's your fuel mixture ? Are you using the correct spark plug ?Good luck & may God bless, Ken

 

[TomR Ont]

Bob in Oakboro,
"Sometimes it will start right back up and other times it will not start back up and you must quit work for a while until it cools off."

I have the 034 if I try to start it with the choke on when warm I have the same problem, which is easy done.
When starting mine cold, if it just caughs as to start, I must take the choke up one notch, if it's warm or hot next notch up. Or I could pull it all day and it won't start.

 

[Don c]

Son has a 026 and from the sounds of yours, his is about the same. 2 different dealers have had there people try all of what has been said here, saw doesn't have a lot of hours, both are saying new carb... 63.00 new carb. Hope we both find problem before I order a new carb. Don c

 

[ericlb]

have you checked the vent on the gas cap? if thats pluged up it will cause the engine to starve for fuel and it will also be real hard to start imeadeatly after it dies, replace the gas cap first and post back

 

[JT]

What plug did you put in it? If a champion or Bosch, replace it with an NGK. Did you check compression? should be at least 90# of compression. When it is acting up, you can check for a carb problem by squirting some good carb cleaner in the intake and see if it will fire then. If it start and runs, it is a fuel problem, if it does not then it is an ignition or compression problem. Possibly a coil breaking down or a shut off switch.
Jim

 

[Bill in IL]

I had noticed some idle problems with my MS260 when it was new. Now after 5 years of cutting firewood it seems much better. Guess it had to break in not sure if that's the story with yours. My 034 runs better when its below 30 degrees.

The 021 is one of the cheaper models made for occasional use. Not much better than a poulan in my opinion. FIL has had nothing but problems with his little 017 its 10 years old and probably cut 5 loads of wood. His MS390 is showing problems too with light use been in the shop 2x last year. Both saws are homeowners models.

I have had noticeable problems with fuel before so keep fresh fuel (less than a month old). I see you said you drained it but maybe you had some varnish in the carb from other bad fuel.

 

[native]

I had a similar problem several years back with my saw. After rebuilding the carburator, it still acted the same. Ended up taking the muffler apart and the spark arrestor(wire screen)was almost completely carboned-up. Removed all the carbon so I could see the screen again and I have not had to work on it again. I"ve cut approximately 12 cords of wood since. Just a thought. Good luck. Let us know when you find out what the problem was.

 

[Anonymous-0]

Check the fuel line for pin hole leaks.