How to Troubleshoot a 1999 Murray Riding Lawn Mower

Check your gas tank and insert new gasoline if necessary.

Dispose of old fuel in your 1999 Murray riding lawn mower if the fuel has been left in the tank between seasons and over the winter months when the mower was not in regular use. Add a bit of fresh gasoline to the fuel mix, turn on the Murray mower and let it run idle until all the gasoline burns from the tank. Fill the tank with fresh fuel and then resume normal operation.

Check the 1999 Murray riding lawn mower's spark plug for brown or black corrosion on its end, noticeable wear and tear or black spots on its white insulator ring. If these exist, replace the spark plug completely by removing the thin, black ignition wire from the plug and sliding it into the rear insertion point on a replacement spark plug.

Alter the air adjustment valve located on your 1999 Murray riding lawn mower's carburetor. If the amount of air entering the valve and into the carburetor is incorrect, the engine will sputter and the Murray riding mower will run poorly. Turn the valve all the way to the right until you can no longer adjust it, and then turn it back to the left two more turns. Attempt to start your engine.

Alter the Murray's air adjustment valve further if the engine still sputters.

Check the 1999 Murray riding lawn mower's fuel tank cap if altering the adjustment valve did not yield results. Unscrew the cap from the tank and clean any debris and crusted build up from its vent hole. This hole allows air in to reach the carburetor and cannot be blocked. Use a pipe cleaner to clean out this small vent hole, then screw the fuel cap back onto the Murray mower.