Our son came over and he said "oh, I know what the problem is." He said there's a little hole in the gas cap that could be clogged." We cleaned the little hole and it started right up. Hope this will help someone else whose mower wants to start, but won't. Just something else to check. Bill

If the battery sat for 2 years, it's probably bad. What's the voltage reading when you try to crank the engine? It shouldn't drop below about 9V.

Nope. just getting my info from an ONAN manual. This is a bit garbled since I'm copying it from a 2 column pdf file- 3. Pull spark plug wires off spark plugs and remove spark plugs. Connect an approved spark tester to each of the spark plug wiresand ground them away from spark plug hole. Turn key on and crank engine over for 5 seconds while watching for spark. If a spark occurs regularly, the problem is not in the ignition system. If no spark occurs, go to step 4. Incorrect wiring can cause elec- tronic ignition damage. Do not attach any lead or jumper with power (such as B+) to coil negative terminal. 4. Connect a jumper lead directly from the positive battery terminal to the positive (+) coil terminal (smaller diameter of the two threaded posts). Crank engine over while watching for spark. If spark occurs, the problem is in the low oil pressure cut out switch (if equipped) or related wiring, the lubricating system (low oil pressure), or in the other circuitry bringing voltage to the coil. If no spark occurs, go to step 5. 5. Connect positive side of voltmeter to negative (-) coil terminal (larger diameter of the two threaded posts) and negative side of voltmeter to engine ground. Turn key on and rotate flywheel slowly by hand while observing voltmeter. Voltage should switch between battery voltage and 1-1.5 for each revolution. If voltage does not switch properly, replace ignition module. 6. Install spark plugs and wires. If ignition module is being replaced, be sure to connect red lead from new ignition module to positive (+)terminal of coil, black lead from module to negative (-) terminal of coil. Continuity Test 1. Pull spark plug wires off spark plugs and remove spark plugs. 1-1 Accidentalstarting of the engine AWARNING can result in severe personal injury or death. Remove spark plugs before proceeding. 2. Turn ignition on. 3. Connect a voltmeter between the negative (-) coil terminal (larger diameter of the two threaded posts) and a good engine ground. 4. Rotate the flywheel slowly by hand in the clockwise direction until the voltmeter reading switches from approximately 1 volt to battery voltage. Atthis point, one of the chaff screen screws should lie between the two timing marks on the blower housing. To recheck timing, the flywheel must be rotated another complete revolution in the clockwise direction. Moving the flywheel back and forth across the reference timing mark will not activate the electronic ignition control. This post was edited by bill_kapaun on Mon, Feb 17, 14 at 20:17

***" an engine was said to be a self-producing power source...as long as you had some type of liquid, solid or gaseous fuel supply. And a motor required a separate power source, such as a hydraulic or pneumatic pump unit, or electric power generating plant to make it operate."*** larso, you are the first contestant to answer correctly. And of course, it is absolutely playing with semantics. After all, you don't think I believe all the "Motor Oil" in the stores is for electric motors, do you? The only time I ever saw "Engine lube oil" actually packaged that way was back in the 1970s when I worked for International Harvester. IHC always had their own branded "motor oil" (and other lubricants and antifreeze). In 1975, IHC "reworked and revamped" their "house brand" engine lube oil family to the "low ash" formula that was purported to help gasoline engines meet the ever more stringent EPA emissions standards. IHC discontinued using "paper with metal end" quart and gallon containers. The new "Engine Lube Oil" was packed in all metal (steel) quart and gallon "cans", and for the first time ever, IHC offered a "five gallon can" of oil. Oh, while IHC was making an attempt to be "PC" about "engine oil", The company division I was affiliated with was known as "International Harvester, MOTOR Truck Division". Go figure!