If your Kohler small engine is backfiring, making a loud pop or bang possibly accompanied by the engine shutting down, check the fuel. There may be water in the gas tank. If the engine is a two-stroke which takes a mixture of oil and gas, make sure the oil-to-gas ratio is correct.
The carburetor may need an adjustment to prevent too much gas from going into the cylinder. It would also be a good idea to clean out the carburetor with carburetor cleaner.
If the previous steps donâ€™t fix the problem, check to see if the valves are sticking open. If you arenâ€™t comfortable with this troubleshooting step, it may be necessary to have an experienced small engine mechanic look at the engine at this point.
You can find the model and serial numbers located on a silver sticker typically attached on the blower housing of the engine.