Trust the Lawn Mower Repair Experts

Don't let your grass grow out of control because your push lawn mower won't start, vibrates too much or doesn't cut well. Let Sears Home Services help you get your mower going again with expert DIY troubleshooting and repair advice. We also have the genuine repair parts you need on our Sears PartsDirect website.

Follow the troubleshooting advice shown below to fix common lawn mower problems.

Can’t Pull the Starter Rope

When you tip your lawn mower over for maintenance or cleaning and then can’t pull the starter cord, the cylinder is likely flooded with oil. Follow these steps to fix the problem:

1. Remove the spark plug and move the spark plug wire out of the way.
2. Pull the starter rope several times to clear oil out of the cylinder. You'll see oil spray out of the spark plug hole.
3. Wipe off the oil and reinstall the spark plug. Then reconnect the spark plug wire.
4. Pull the starter rope to start the engine.

A lot of white smoke will come out of the muffler as the engine sputters to life, because the engine is burning off the oil inside the cylinder. Once the engine burns off the oil, the mower should run smoothly.

Our How to Fix a Pull Cord Stuck After Tipping the Mower YouTube video illustrates this DIY repair procedure.

If you can’t pull the starter rope and you didn’t tip the mower over, a branch or other debris may be blocking the mower blade from moving. Put on some work gloves and tip the mower on its side with the air filter up. If you see a branch or other item under the mower deck that’s preventing the blade from spinning, remove it. Reconnect the spark plug, and you should now be able to start the mower.

If you didn't find anything blocking the blade, there might be a problem with the recoil starter. Disconnect the spark plug again and release the rope from the lawn mower handle. Remove the screws from the blower housing and pull the housing off the engine. Pull the starter rope to see if the recoil starter works. If the starter is locked up or cracked, replace it. Pull off the recoil starter guard and then release the recoil starter from the tabs on the blower housing. Remove the recoil starter and snap the new one into the tabs. Reinstall the recoil starter guard and then you're ready to reattach the blower housing to the engine.

If these DIY mower repair tips don’t help you fix the problem, have a repair technician examine and repair the problem.

Why won't my lawn mower start?

When you can't start your mower, make sure the tank has fuel and that the fuel is fresh; stale fuel can become watery and won't ignite well. Tune up the mower's engine to give it the best chance of starting. Check the spark plug and replace it if it's covered with oil or other deposits.

If your mower uses a battery, charge or replace the battery if it won't power the starter to spin the engine. If you have to pull the starter rope to start the engine, replace the recoil starter if it doesn't spin the engine when you pull the rope. Replace the starter rope if it's broken.

Replace the safety switch or the ignition coil if the spark plug isn't getting current through the ignition system. The engine won't start if you hit a rock or stump and shear off the flywheel key, so replace the flywheel key if it's broken. Follow the DIY troubleshooting tips in our Lawn Mower Won’t Start: Spark Plug and Ignition Problems video when the engine isn't getting any spark.

Carburetor problems often prevent a mower engine from starting. Replace or rebuild the carburetor if it's clogged. Our Lawn Mower Won’t Start: Fuel, Ignition and Compression Problems video offers you more help with troubleshooting fuel problems.

If you’re unable to get your lawn mower started after following these DIY troubleshooting tips, have a professional repair expert fix the mower.

How to Replace a Lawn Mower Carburetor

The carburetor blends air with fuel to form a combustible mixture that ignites in the cylinder to drive the piston. If the carburetor is clogged or damaged, the engine runs rough or won’t start. If the carburetor is clogged or damaged, replace it by following these steps.

1. Wear work gloves to protect your hands. Working in a well-ventilated area, disconnect the spark plug wire from the spark plug.
2. Release the catch and pull the air filter cover off. Remove the air filter. Remove the screws from the air filter base. Release the breather tube and pull off the air filter base.
3. Place a shop rag under the fuel tank to catch spills. Place a fuel-safe container under the gas line connection to the fuel tank. Release the spring clamp and disconnect the fuel line from the gas tank. Drain the gasoline into the container. Wipe up any spills.
4. Release the starter rope from the mower handle. Remove the screws from the blower housing. Pull the blower housing off the engine.
5. Separate the carburetor mounting bracket arms to release the carburetor and disconnect the carburetor from the carburetor adapter. Holding the carburetor above the bracket, disconnect the governor and choke linkage rods and remove the carburetor. Release the fuel line spring clamp and pull the fuel line off the carburetor.
6. Push the O-ring into the outlet port of the new carburetor. Install the retainer on top of the O-ring. Connect the fuel line to the new carburetor and secure it with the spring clamp. Hold the carburetor over the mounting brackets and connect the governor and choke linkage rods. Push the carburetor into the bracket arms and push the outlet port fully onto the carburetor adapter. Push the air cleaner gasket into the channel on the carburetor inlet.
7. Reassemble the mower by reversing the above steps and reconnect the spark plug wire.

Here's a YouTube video that describes the carburetor replacement procedure described above:

Replacing the carburetor on your lawn mower can restore gas flow to the engine so it starts and runs smoothly.

If you continue to have problems with the lawn mower starting and running properly after replacing the carburetor, have a professional service technician diagnose and fix the mower.