Weak spark hard start stihl 021 - RTO Spur Sprocket For Stihl 017, 021 Chainsaws

check the spark plug is there fuel getting to the carby might have to adjust idle screw

Check the timing gap between the ignition module and the fly wheel.

Hi, you cant go wrong their both stihls. The 021 is a more powerful saw and the 017 is lighter, so it all depends on your intended use. Regards Phil.

check for spark the coil might be going bad

Make sure all the wires are hooked up to module.Then unplug ignition switch and test for spark.If you get spark then switch is bad.

Isuggest you clean the carburetta does not take much grit or dust to foul up the works

did you try a new spark plug

Release the chain brake

My guess is since you have ignition, it is a fuel issue: 1- the carb or the fuel lines or pump are plugges with dirt, 2- fuel pump is not working,3- carb needs cleaned 4- air filter is plugged which is very common also. When the saws sit for 6 months or so, the cylinder tends to get gummed up cause our gas is SO good & when this happens with one of my saws, I put spray lube in the spark plug hole & turn it over. When I am thinking, I store my saws with the gas tank down, so that gas isnt running into the carb/engine.

For the 021...on the muffler, there is a spark arresting screen, this is to prevent sparks from coming out of the muffler. It is common for this screen to become clogged with carbon from the engine. You will need to clean/replace this screen in order for it to run correctly.