Troubleshooting a Riding Lawn Mower That Won't 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.
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.

My brother has an old riding mower (90s I think) that won't start. He put in fresh gas, a new battery, and fresh oil, but the engine won't start. He says it's just making a click, the motor shakes, but nothing happens.

I have a Scott's riding mower with a 17Hp Briggs and Stratton motor. It won't turn over after mowing the grass last week. It needed a new battery and air filter.

I was cutting the grass. I got off my Snapper rider to pick up trash. The mower died and won't start back up. It is like a dead battery, but the battery is good. Could it be the solenoid?

My mower won't fire even though I put a new plug in.

I have a Castle Garden rideon mower. I only had it running a couple of months ago (cut the garden), it was sitting up in the garage since then, now it won't start. The lights come on, everything seems OK, but it just won't start. The orange light beside the red button to get the blades cutting came on. Any help or ideas please.

I was mowing and the mower shut off. It still had plenty of gas. I changed the fuses, but all the engine did was click. The battery is fully charged. I crossed the posts on the solenoid with pliers, the engine cranked, but when I turn with the key there is only clicking.

I have a older Yard Machine riding lawn mower that has been sitting for a couple years. First of all I can't seem to get it into neutral to push it, second of all when I do try to start it it's tries to turn over, but it is with the deck engaged and I can't get the deck to turn off to get it started. Any help would be greatly appreciated. Thank you.

My lawnmower will not start. It doesn't make a sound. I have charged the battery and it reads over 12. I have done the ignition switch and spark plugs. I have replaced the solenoid and tried different wiring ways with it. I don't have any voltage drops to the starter. A couple wires were cut and I spliced them back together. Please help!

A couple of weeks ago while I was mowing the lawn with my 12.5 hp Yarkworks lawn tractor for some reason the machine started revving really fast. I turned off the ignition as quickly as I could. I then went to restart my tractor. However the machine would not turn over until it cooled down. The symptoms haven't changed. I can mow the grass for hours as long as I don't turn the machine off. Then I must wait until it cools down again. Someone told me I may have a warped head since the machine revved like it did. Help.

I changed the oil filter, added new oil, new carburator, new spark plug, new fuel filter, new battery, new air filter, and new gas, but it still will not start. The flywheel is turning over, the muffler puffs occasionally when I choke, but nothing happens. I am stumped. I poured a teaspoon of gas in the spark plug area to see if there was fuel constraint which resulted in a few coughs through the muffler. What do I do next? any suggestions? Thank you!

I have spark, I can smell the fuel, it appears to have compression, but still won't start. There is a new battery, it turns over with good power, but won't start. What else should I check?

I just put in a new battery and plug. The fuel is good it. It will start on pull cord, but won't pick up with the key turns over ok.