The beauty of your lawn depends upon a properly operating mower, and if your Craftsman 6.0 HP (horsepower) lawn mower suffers from bad fuel, a disconnected or bad spark plug, a misaligned air adjustment valve or even a fuel tank cap problem, then your lawn will also suffer. You can avoid expensive repairs to your Craftsman 6.0 mower and troubleshoot the problems yourself even if you lack any previous lawn mower repair experience and have never attempted to fix a Craftsman product before.
Ensure your Craftsman 6.0 mower is off. Check the fuel tank to ensure there is gas in the tank; otherwise, you must refill it.
Replace old fuel. Do not attempt to use gas left over from the winter months when the lawn mower was not in use. Add just enough fresh gas to the old gas mixture to start the mower's engine, then allow the mower to sit idle with its blades disengaged. Run off all the old fuel in the tank, then fill the tank entirely with fresh gas.
Look at the spark plug at the side of the front of the Briggs & Stratton engine and check for visible corrosion, general wear or "blistering" of the white insulator ring at the end of the plug that would result in black spots. Any of these conditions indicate a bad spark plug.
Disconnect the thin black ignition wire from the rear of the mower's spark plug if you determine that it is bad. Reinsert the wire into new replacement spark plug.
Check the air adjustment valve on the Craftsman 6.0 mower's carburetor. The valve twists to let more or less air into the carburetor. If too much or too little air reaches the carburetor, the mower may not start or may run rough and sputter. Turn the air adjustment valve all the way to the right and then back two turns.
Check how the mower's engine runs after your adjustment. Readjust the air adjustment valve further to the right and left as necessary if the engine continues to run poorly, then check its performance again.
Make sure the fuel tank cap is in good order if the engine is still sputtering. A clogged fuel tank cap will limit the amount of air the carburetor can receive. Use a pipe cleaner to force any debris and fuel clogs through the small vent cap hole, then wipe up the muck with a cloth.
Set the fuel tank cap back into its place on the Craftsman 6.0 mower.