January 03, 2020

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

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.

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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.

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