This unit has a fuel pump and has an electric clutch to engage the mower blades. If you use a fuel pump on your engine, you must purchase an engine that has a fuel pump on it. If you have an electric clutch and you purchase an engine with less than a 9 amp alternator, you will have to use your alternator and regulator of your old engine. If you purchase a recoil start engine, you would have to use your flywheel and starter of the old engine.
