2. Use a screwdriver to turn the idle screw clockwise to increase the idle speed, or counterclockwise to decrease it.
3. Start the lawnmower and let it run for a few minutes.
4. Check the idle speed with a tachometer. The ideal idle speed for most Toro lawnmowers is between 1800 and 2200 rpm.
5. Repeat steps 2-4 until you have reached the desired idle speed.