20 Most Recent RTO Spur Sprocket For Stihl 017, 021 Chainsaws Questions & Answers

well haven't had any problem finding a replacement

there is a jet inside the carb that is plugged up leaning it out

Somewhere on the carb linkage you will see a set screw touching it. Turn the screw so it does not push the linkage so far.

This is a timing problem.
Check the plug, and check magnete.
Then if you have to, remove the carb and replace the inlet gasket.
Good luck with that Scott.

If it is getting smokey exhaust befor stopping it is getting too much fuel. If not smokey it is not getting enough fuel. If smokey first take out the air filter and clean it. If it runs fine your done. If not smokey open the high needle valve (marked with an H) on the the carb a little (no more than a 1/4 turn).

they can get plugged up with chips and sticks, take the cover of and blow it out with compressed air.

idles at 2800 and wot 14000. I tune to about 13800 and that is with bar and chain on If you need further help, I’m available over the phone at https://www.6ya.com/expert/kelly_69a0cf1b13789df1

I'm not sure there are any "endorsed" tuning specs from Stihl as weather, temperature, fuel quality etc all contribute to engine performance.
Pictures of all types are all over the web.

As for the carb tuning procedure, maybe I can help?

Start with fresh fuel, all filters clean, and bar and chain installed. Also, fill the chain oil tank with bar/chain oil and VERIFY that the chain oiler works properly.
Initial fuel mixture settings (the H and L screws) should be 1.5 - 2 complete revolutions counter clockwise from lightly seated. Sight the carb's throttle plate and adjust idle screw counter clockwise until the plate stops moving.(Throttle closed completely.) Then go back clockwise 3 complete revolutions. This will produce an acceptable startup condition on a HEALTHY saw.
Clamp the bar in a STURDY bench vise and roll the chain with the shank of a screwdriver to verify it is clear. BE SAFE!
Choke the saw and pull the starter rope until the engine "burps".
NOTE: If no burp after 6 pulls, stop! Something is wrong.
After the burp, set choke to half and pull starter until it runs. The settings I gave should produce a slightly rich condition and a slightly high idle. (Chain will be in motion!)

Blip the throttle trigger and idle it down just enough to keep it running during the tune procedure.
Step 1) Using the "L" screw (closest to the engine), turn it clockwise until the engine smooths out or possibly increases RPM. Back it out slightly until the engine has a slight "LOPE" sound to it. (Like a drag car on nitro).
Step 2) Accelerate the engine to full throttle and go to the "H" screw (closest to the air filter) and slowly turn it clockwise and note the RPM increase. There will come a point when the saw will "Top-Out" and loose power. Not even enough power to turn an maintain empty chain's RPM! Go back counter clockwise to the edge of that point, and counter clockwise another fourth (1/4) revolution.
Step 3) Idle the saw back down. Again go to the "L" screw and repeat Step 1.
Step 4) Repeat Step 2.
Step 5) Idle the saw down until the chain stops moving completely. NOTE: Don't settle for a "crawling chain" condition. If the steps above are performed well and all else is healthy, you should be able to idle the engine down to a ridiculously low RPM and it will not shut off.

Hope this helps,
Dolf-

Pull off the clip and sprocket, then check the spring or wire behind the clutch. There is a notch in the sprocket hub that drives the spring when the hub is spinning. Sometimes the spring comes off the worm gear that it drives. If the spring is not there you need to remove the clutch to check it. It has left handed threads on it)

try adjusting the low speed needle.

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.

Check the pole gap on the ignition module to the flywheel magnets. Use a thin business card for a gauge. If it has the correct gap and you have tried a new spark plug, then the module itself is likely failing. Hope this helps!

If it is new this is much easier. The spring comes in a plastic keeper and only needs to be aligned and pressed into place.
If the spring is loose this is much easier as a dealer, with the correct tools. tighten the spring back into a col and set it in place.
Good luck

Joe

remove the muffler and run it after finding that it runs fine open the muffler and clean the screen inside (it is made to open to clean it)

Stihl 028 OM can be downloaded here:
Stihl Product Instruction Manuals
http://www.stihlusa.com/stihl_ownersmanuals/STIHL028_with_safety_manual.pdf

If equipped with points 0.015" ± 0.001".

If you have more questions or need additional help please reply below and I will get back to you. Thank you for using FixYa and Good Luck. HTH
Lou