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T. Phoenix
T. Phoenix, Technician
Category: Small Engine
Satisfied Customers: 539
Experience:  10 + yrs. working at family shop
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hello , my stihl fs55 weed trimmer wont run at full throttle

Resolved Question:

hello , my stihl fs55 weed trimmer wont run at full throttle tried adjusting at owners manual recomended settings help
Submitted: 6 years ago.
Category: Small Engine
Expert:  T. Phoenix replied 6 years ago.
Hi There!
Thank you for letting me try and help you here.
This can be a few things.
FIrst of all you should make sure your spark plug is good, or new. A fouled plug can cause this.
Make sure your fuel mixture is correct.
Then when you hold the throttle wide open turn the High speed screw either way. In or out from where you're at. You can increase the rpm by that screw.
When you find the highest smooth rpm stop and then turn the screw out 1/4 turn just so you know it's not running lean.
The specs in the book are just starting points. Every engine is tuned a little different.

If that doesn't do you any good you should look into getting a rebuild kit for the carburetor.
Like this one
It's fairly inexpensive for the parts and can take out any guessing as to whether the carb is functioning like it should.
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