April 19, 2023

DIY walk-behind mower repair

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 PartsDirect show you how to fix your gas mower with our troubleshooting tips and videos and step-by-step repair guides. (If you have a riding mower, check out our DIY riding mower & lawn tractor repair help.)

Preventive maintenance can go a long way toward keeping your walk-behind mower in good operating condition. Learn how to tune up a mower at the beginning of each season and how to replace the cutting blade to get the mowing season off to a good start.

If you pull the starter rope and nothing happens, watch our video for troubleshooting tips on why a lawn mower won't start to figure out what's wrong. If your push mower starts but won't move, there's a good chance the mower's drive system might be to blame. Get your mower moving again using the DIY tips in our video troubleshooting motion drive failures in a lawn mower.

If you have a different problem with your gas mower, check out our articles and videos page for additional troubleshooting tips. Once you find out what part to replace, our DIY repair guides give you detailed instructions to complete the job and get your lawn mower working again. To find the owner’s manual or a complete list of replacement parts for your gas walk-behind lawn mower, search for your model number.

gas walk-behind mower

Symptoms for gas walk-behind mowers

Choose a symptom to see related walk-behind mower repairs.

Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent…

Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, ba…

Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade…

Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel…

Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key…

Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up…

Repair guides for gas walk-behind mowers

These step-by-step repair guides will help you safely fix what’s broken on your walk-behind lawn mower.

How to replace a lawn mower recoil starter on an OHV engine

How to replace a lawn mower recoil starter on an OHV engine

Replace the recoil starter if it doesn't move when you pull the starter rope.…

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower transmission

How to replace a lawn mower transmission

Learn how to replace the transmission on your lawn mower if it's locked up or won't drive the wheels.…

Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower carburetor

How to replace a lawn mower carburetor

The carburetor mixes air with fuel to drive the piston. Replace the carburetor if it's clogged or damaged.…

Repair difficulty
Time required
 15 minutes or less
How to rebuild a lawn mower carburetor

How to rebuild a lawn mower carburetor

The carburetor mixes air with fuel to drive the piston. Rebuild the carburetor if it's clogged or leaks.…

Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower blade

How to replace a lawn mower blade

Check your lawn mower blade regularly and replaced it if it's bent or damaged. …

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower front deck tray

How to replace a lawn mower front deck tray

Learn how to replace the front deck tray on your lawn mower if it's cracked or damaged.…

Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower ignition coil on an OHV engine

How to replace a lawn mower ignition coil on an OHV engine

Replace the ignition coil if it isn't sending electric current to the spark plug when you pull the recoil starter rope.…

Repair difficulty
Time required
 30 minutes or less
How to replace a lawn mower drive belt

How to replace a lawn mower drive belt

Learn how to replace the drive belt on your lawn mower if it's worn or broken and won't drive the mower.…

Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower drive cable

How to replace a lawn mower drive cable

The drive cable engages the transmission to spin the drive wheels and move the mower across the grass. Replace the drive…

Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower flywheel key on an OHV engine

How to replace a lawn mower flywheel key on an OHV engine

The flywheel key couples the flywheel to the engine crankshaft. Replace the flywheel key if it's broken.…

Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower spark plug

How to replace a lawn mower spark plug

Take a few minutes to replace the spark plug during your lawn mower's annual tune-up or if the spark plug is burnt or cr…

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower flywheel key on a flathead engine

How to replace a lawn mower flywheel key on a flathead engine

When you hit a hard object with your mower, the flywheel can shear to protect more expensive components. Learn how to re…

Repair difficulty
Time required
 45 minutes or less
How to replace a lawn mower starter rope

How to replace a lawn mower starter rope

These step-by-step instructions show how to replace a broken starter pull rope on a walk-behind lawn mower.…

Repair difficulty
Time required
 30 minutes or less
How to replace a lawn mower ignition coil on a flathead engine

How to replace a lawn mower ignition coil on a flathead engine

If the spark plug doesn't fire when you try to start the mower, you could have a defective ignition coil. Follow these s…

Repair difficulty
Time required
 30 minutes or less
How to replace a lawn mower wheel

How to replace a lawn mower wheel

Learn how replace a damaged wheel on a walk-behind lawn mower—it's a quick, easy fix.…

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower recoil starter on a flathead engine

How to replace a lawn mower recoil starter on a flathead engine

If the starter rope on your walk-behind lawn mower won't retract, replace the mower recoil starter assembly.…

Repair difficulty
Time required
 30 minutes or less
How to replace a lawn mower safety switch

How to replace a lawn mower safety switch

The safety switch stops the engine when you release the lever on the handle. This repair guide explains how to replace i…

Repair difficulty
Time required
 30 minutes or less

Articles and videos for gas walk-behind mowers

Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.

Lawn mower parts and supplies to stock up on video

Lawn mower parts and supplies to stock up on video

Keep these 5 things on hand so you’re ready to mow grass all season long.…

Easy DIY lawn mower repairs

Easy DIY lawn mower repairs

Learn what lawn mower repairs you can do easily by yourself.…

Is it time to switch to an electric lawn mower?

Is it time to switch to an electric lawn mower?

See a comparison of cordless lawn mowers and gas mowers so you can decide which is best for you.…

Top 10 electric lawn and garden tools for 2023

Top 10 electric lawn and garden tools for 2023

Learn about the top 10 must-have electric lawn & garden tools for 2023…

How to enjoy all the online benefits we offer on our Sears PartsDirect website

How to enjoy all the online benefits we offer on our Sears PartsDirect website

Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier.…

Tapping into a new feature in the Search Bar on Sears PartsDirect

Tapping into a new feature in the Search Bar on Sears PartsDirect

Learn about a new feature added to the Search Bar on Sears PartsDirect…

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…

What are the main components of a lawn mower?

What are the main components of a lawn mower?

Learn about the main parts of a lawn mower and when to replace parts.…

What causes lawn mower engine surging?

What causes lawn mower engine surging?

Learn how to fix your lawn mower when its engine surges…

Can you use starting fluid on a mower?

Can you use starting fluid on a mower?

Learn how to safely use starter fluid on a lawn mower…

How to keep lawn mower gas from going bad

How to keep lawn mower gas from going bad

Keep your lawn mower fuel fresh following these easy tips.…

How to winterize a lawn mower

How to winterize a lawn mower

Your lawn mower will last longer and run better if you take these steps before storing it for winter.…

How to remove a lawn mower blade using a removal tool

How to remove a lawn mower blade using a removal tool

Learn how a blade removal tool makes replacing the blade easier and safer…

How to fix a pull cord stuck after tipping mower

How to fix a pull cord stuck after tipping mower

Learn what do do if your started pull cord is stuck after tipping your lawn mower for maintenance or cleaning.…

How to prevent grass buildup on your walk-behind lawn mower

How to prevent grass buildup on your walk-behind lawn mower

Learn 3 tips to keep the underside of your mower deck grass-free.…

Types of walk-behind mower blades video

Types of walk-behind mower blades video

Learn about the different kinds of mower blades and how to maintain them.…

How to tune up a lawn mower video

How to tune up a lawn mower video

See how to tune up your mower once a year to keep it running well.…

How to sharpen a lawn mower blade

How to sharpen a lawn mower blade

A dull blade leaves grass tips tattered. Sharpen it several times a season. Here's how.…

Lawn mower won't start troubleshooting video: can't pull recoil pull cord

Lawn mower won't start troubleshooting video: can't pull recoil pull cord

A blade obstruction, bad recoil starter or locked-up engine can prevent the pull cord on your mower from working. See ho…

Lawn mower won't start troubleshooting video: fuel, ignition and compression problems video

Lawn mower won't start troubleshooting video: fuel, ignition and compression problems video

Check whether a clogged air filter, bad spark plug or contaminated gas is why your lawn mower won’t start.…

Lawn mower won't start troubleshooting video: spark plug and ignition problems video

Lawn mower won't start troubleshooting video: spark plug and ignition problems video

Find out how to test and fix problems with the spark plug, stop wire, ignition coil and flywheel.…

Lawn mower won't move troubleshooting video: motion drive failure

Lawn mower won't move troubleshooting video: motion drive failure

Find out whether a broken or disconnected drive cable is the reason why your lawn mower won't move.…

How to mow a lawn for healthier grass

How to mow a lawn for healthier grass

How often and tall you mow your lawn has a big impact on its health. Check out these 3 rules.…

6 sure ways to destroy a lawn mower

6 sure ways to destroy a lawn mower

Tired of mowing? Here's our tongue-in-cheek advice rendering your mower useless.…

How to change a lawn mower wheel video

How to change a lawn mower wheel video

It's easy to install a replacement wheel on your walk-behind lawn mower if the wheel is damaged. Just follow the steps i…

6 weeks to a better lawn

6 weeks to a better lawn

Do these 5 things this spring for a lawn that's healthier all summer.…

How to keep grass clippings from sticking to a mower deck

How to keep grass clippings from sticking to a mower deck

Prevent your mower deck from rusting by following our advice for keeping grass clippings from sticking.…

Walk-behind lawn mower common questions

Walk-behind lawn mower common questions

Learn more about your lawn mower from the answers to these often-asked questions about walk-behind lawn mowers.…