The Forestry Forum

My Stihl starts up ok, but when I give it gas, the engine will barely accelerate, and the chain barely turns.  My 8 year old son and I would like to fix it ourselves.  Where should we start?  Thank you in advance.  

Is this an older saw, what model?

There are a few basic maintenance things common to most small engine that would be a good start.

Replace the fuel filter and use fresh fuel
Replace the spark plug
Clean/replace air filter
If it is old and has them, check the points and points assembly, if readily available, just replace the points and condensor
If it has sat along time with gas in it, the carb will need dissassmbly and cleaning.  This isn't very hard, just do it in a well lit and clean area so anything you drop will be found.  Use some carb cleaner and whatever else you need to wash the chunks of stuff away.  Check if the flaps for the pump are in ok condition.

I would take a guess at the fuel filter or air filter.  The fuel filter is weighted in the fuel tank.  To get it out, drain the gas out and tip the saw or use a wire to fish it out.  Sometimes more line will have to be fed into the tank (the hose passes through the tank from the carb) to allow you to hold the hose to push the new filter on.

Hope this helps.
Ken

first take off the bar and chain to see if they are the problem.  

was it running fine and just started or has it been sitting?

Good call! skipped past the simplest thing!
Ken

Quotefirst take off the bar and chain to see if they are the problem.  

was it running fine and just started or has it been sitting?

Hey JimL, You might check the spark arrester screen in the exhaust of the saw. Some times these screens get plugged with carbon. This can cause the saw not to run well, such as poor power and  slow acceleration. The easiest way to correct this problem is replace the screen with a new one. You can also can clean these with a wire bush and a propane torch. It is just some thing  you may want to check. Hope you get the saw running good again soon.   Hunter700