If Your Riding Mower Will Not Start

If your riding mower will not start (most of these tips are applicable to push mowers also):

1. Make sure you have fresh fuel; dirty or old fuel will not burn. Consider an octane boosting additive.
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2. Make sure the oil level is correct; too much or too little oil will prevent the mower from starting.
3. Most riding mowers start only when in neutral and when the blades are not engaged; make sure the trans is in neutral and the blades are not engaged. Engage the brake and/or clutch.
4. Ensure it's getting fuel to the carburetor by pulling the line at the closest inlet near the carburetor, then cranking; it should spurt fuel. Make sure if you put new fuel in the tank, that you purge the old fuel from the lines by this method.
5. If you are getting fuel, the carburetor may be dirty from fuel setting in the bowl for a long time; take the carburetor apart by removing the brass bolt from the bottom of the bowl, and cleaning the bottom parts with carburetor cleaner.
6. Make sure the seat switch engages when you sit squarely in the seat.
7. Wear safety glasses when you use pressurized air to clean dirt off of the entire engine; leaves, dirt, and other foreign particles may prevent the engine from breathing. Keep the top of the flywheel and the fins on the flywheel clean.
8. If the magneto(s) or the flywheel are rusty, you won't get spark; use emery cloth to sand the rust off of the flywheel and the magneto(s). You have to remove the magneto to clean the rust off. Get all the rust off; the flywheel needs to shine where it makes contact with the magneto(s).
9. Dead batteries are usually bad batteries. If the battery is dead, and does not charge, you probably have a bad alternator, or a bad battery.
10. Make sure you 'choke' the carburetor the first time you crank it. After some cranking, you may need to adjust the choke. Make sure the throttle is adjusted to the 'Start' position.
11. The air filter must be clean: If your carburetor is starving for air, the mower will not start. Clean the filter with soapy water and a soft brush. Hold the filter to a light, or the sun; you should be able to see light through the filter. Try starting without the filter, but do not operate the mower without the filter.
12. Grass build-up in the mower deck may prevent the mower from starting. Make sure to pull the spark plug when you tip the mower to bust the clogged grass away from the deck. Be aware that tipping the mower can cause oil to leak from the engine block into the cylinder, which will result in smoke from the muffler due to oil burning; it should just last a minute or less.