September 1, 2016

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

By Sears PartsDirect staff
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.

If your lawn mower doesn't start, the problem could be with the spark plug or ignition system. This video from Sears PartsDirect shows how to troubleshoot and fix spark plug and ignition problems, including using a spark plug tester to test the spark plug.

The video also shows how to use a multimeter to check for a short in the wire that connects the stop switch to the ignition coil, and it walks you through how to check the ignition coil and flywheel. Once you figure out the problem, we show you how to fix it. You'll be cutting your grass in no time.

Symptoms for gas walk-behind mowers

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

Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel
Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade
Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent
Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up
Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key
Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, bad ignition coil

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 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
April 1, 2013
By Lyle Weischwill
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
April 1, 2013
By Lyle Weischwill
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 it if it's not working correctly.

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.

May 31, 2019

How to tune up a lawn mower video

By Sears PartsDirect staff

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

September 1, 2016

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

By Sears PartsDirect staff

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

June 1, 2016

How to mow a lawn for healthier grass

By Erin Hynes

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