Spring is here, everything is green, and the grass is growing...but your lawn mower won't start. No matter how many times you pull, the engine just doesn't turn over. What do you do?
Your lawn mower needs three things to start:
1. Fuel
2. Air
3. Spark
If you're having trouble getting your lawn mower started, you're best bet is to check those three things first. Clogged air or fuel filters, gummed up carburetor needles or floats, and bad spark plugs can mean your lawn mower isn't going to be ready when you need it.
So before you strain something trying to get it running, here are some troubleshooting tips to help you figure out why your lawn mower won't start and what you need to do to get it running so you can keep your head above the grass this summer.
** Remember to always refer to your operator's manual first before doing any maintenance.
Why Won't My Lawn Mower Start?
Old Gas in Your Lawn Mower
If you still have gas in your lawn mower from last season, this is the perfect place to begin. About 30 days after being pumped, gas can start to go stale or oxidize, especially if it's just been sitting in your mower. It becomes less stable and gums up the fuel system as it evaporates. A stuck inlet needle or clogged jets from bad gas can definitely lead to starting problems. Also, ethanol in the gas attracts moisture and causes corrosion. The Outdoor Power Equipment Institute recommends you use gas with 10% ethanol (E10) or less in your small engine equipment. If your mower won't start, you may need a fresh tank of gas.
What To Do
- Drain the fuel tank and add fresh gas
- Use a fuel stabilizer
Dirty Air Filter
Your lawn mower doesn't run if it can't get air in the carburetor. Also, a damaged air filter can let in contaminants that can clog or damage the engine. Take a look at the air filter and see if it may be the cause of the problem.
What To Do
- Clean or replace the air filter
Dirty Spark Plug
Your spark plug may be dirty, loose or disconnected entirely, which means you're not getting any spark. Take a look at the wire and the spark plug itself. Make sure it is dry and clean. If you recently did some maintenance on the mower and disconnected or replaced the spark plug, it's possible the connection isn't tight.
What To Do
- Clean or replace the spark plug
What if the starter rope won't pull?
The crankshaft is connected to the blade shaft on your recoil start walk behind lawn mower, so if the pull cord is stuck, it could be because something is blocking the movement of the blade. Disconnect the spark plug for safety, then take a look under the deck. Clean out any grass or rocks that may be locking up the blade.
If the mower deck housing is clean, here are a few other reasons that might make the pull cord hard to pull:
1. Flywheel brake is engaged
2. Recoil spring is stuck or broken
3. No oil
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