Small Engines (Lawn Mowers, etc.): Popping noise in riding lawn mower, safety switches, electrical problem

Question
Hello, I have a sears riding lawn approx 2 years old, 24 HP twin engine. All of sudden it started making popping noise when I was cutting the lawn. I started it again at night and it was fine at low speed when I moved the accelerator high it starting making popping noise. Any idea?

Answer
Jim:

Lets isolate the engine from the application.  There will be either a BLACK or GRAY wire from the wire harness that is attached to the engine somewhere.  Look for the wire coming out from under the blower housing  (inside the engine)

Disconnect this wire and start the tractor.  If you problem goes away, you have an electrical problem and need to start looking at your safety switches.  You will need to reattach your wire to shut the engine off however.

How fresh is your fuel?  I have seen fuel contaminated with water or old fuel give the symptoms you describe.  Please make sure you have fresh fuel from the pump in your tank.   Make sure your fuel tank is clean, your fuel filters are clean, etc.

This is a simple one...Did you replace your spark plugs?  you could have a bad plug.  

Does the engine lack in power, there is a slim chance that one of the cylinders is not firing due to a bad ignition coil or even worse a broken connecting rod.

Hope these tips help.