idle goes fast/slow

[redjackrussel]

have a craftsman-24HP riding mower-4years old. Replaced air filter & gas filter in spring, full tune up spring. Now, and just recentely fluxuation in idle speed/fast/slow. Been a dry summer. Any ideas? Runs smooth when blades are engaged.

[Mr T]

Plugged up carb
Plugged up throttle/governer assy.

Make sure all of the mechanical linkages outside the engine around the carb are free. Grass clippings+dirt+oil+time makes a sticky mess. Spray down with carb cleaner.

If it still does it, your bowl float may be sticking. Remove the bowl and clean it out. Clean out the needle valves while you are at it. Your manual should have adjustment procedures. You will need to follow them once you take the valves out. Its not too complex of a procedure. While you are around that area, make sure the bolts attachign the carb to the engine are tight and the gasket looks ok. (you need to replace that gasket if you remove the carb from the engine).

have fun, post back what you find to help others out.