How to Set Stihl Chainsaw Points

Set your Stihl chainsaw to optimize performance

Stihl chainsaws have a unique feature that allows you to control the mixture of air and fuel that goes into the carburetor. These adjustable screws let you set the precise mixture to ensure optimal performance. These points need to be adjusted on a regular basis to make sure the engine is getting just the right amount of fuel-air mixture. These screws should be set if the saw is sluggish when throttle, dies when idling or the chain spins when idling.

Things You'll Need

• Small flathead screwdriver

Instructions

Set the Idle Screw

1. Start the saw to allow the engine to warm up. You should never try to adjust the carburetor on a cold engine.

2. Locate the three carburetor screws on the bar side of the saw, behind the chain brake band.

3. Use the screwdriver to turn the LA or idle screw all the way in clockwise. Adjust the screw back one-quarter turn to get your basic safe setting.

Set Low-Speed Screw

1. Use the screwdriver to twist the L or lowspeed screw all the way in clockwise. Turn the screw back one-quarter turn and remember the position of this screw.

2. Turn the screw out counterclockwise until you hear a heavy gurgling sound from the engine. Twist the screw back in one-quarter turn and remember the position of this screw.

3. Adjust the screw in between these two high and low settings to find the optimal low-speed setting. Your engine should produce a nice clean sound when running at low speed.

Set the High-Speed Screw

1. Use the screwdriver to twist the H or high-speed screw in all the way. Throttle the saw and back off this setting one-quarter turn. Listen to the sound the engine makes and remember the position of this screw.

2. Turn the screw back out counter-clockwise until the engine produces a heavy, sluggish sound. Turn it back in clockwise one-quarter turn.

3. Adjust the screw in between these two high and low settings to find the optimal high speed setting. Your engine should sound strong and clean, but not too high or whiny.

4. Fine-tune the low speed screw and idle screw after finishing the high-speed screw.

Tips & Warnings

• Always clean your air filter and muffler screen before adjusting the carburetor.

• Never set your high speed screw above the highest factory RPM settings.

• If in doubt, use a tachometer.

• If you set your high-speed screw too high you will overheat and ruin your engine.

References

• TEK Indoor: Carburetor Settings for a Stihl Chainsaw
• Madsen's: Saw Carb Tuning
• Stihl: Chainsaw Care and Maintenance Guide