January 3, 2020

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

By Sears PartsDirect staff
Grass buildup on a lawn mower deck can cause rust and corrosion on the deck as well as an uneven cut on the lawn.
Grass buildup on a lawn mower deck can cause rust and corrosion on the deck as well as an uneven cut on the lawn.

Grass that builds up on the underside of your walk-behind lawn mower deck disrupts airflow needed to lift the grass for a clean, even cut. It also can lead to rust and corrosion of the mower deck. This video gives 3 tips on how to prevent the grass from clumping under your mower deck.

For more DIY help, including troubleshooting videos and step-by-step repair guides, check out our walk-behind mower repair help’ section. In addition, find the lawn mower parts you need to fix your mower.

The following tips can help avoid grass buildup under a lawn mower deck. Caked-on clippings disrupt the airflow and encourage rust and corrosion.

Use a spray lubricant

MO-DECK keeps grass from sticking and prevents rust.

Mow only when it's dry

Grass is sticky when wet.

Keep clippings short

Cut no more than 1/3 of the grass height. Shorter clippings blow away easier—and a trim is less of a shock for the grass than a crewcut.

Symptoms for gas walk-behind mowers

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

Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up
Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent
Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade
Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key
Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel
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.

March 1, 2016
By Lyle Weischwill
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
 30 minutes or less
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 replace this tiny but essential part.

Repair difficulty
Time required
 45 minutes or less
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 step-by-step instructions to replace it.

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.