The Best Mower Deck Undercoatings


If you’ve been using a lawn mower for a while, you notice that the deck starts to wear out and rust. This is due to grass and debris sticking to the underside of your mower and keeping the metal wet. One of the best ways to protect your lawn mower deck from rusting is to apply coatings on the deck. And one of the internet’s most searched questions concerning lawn mowers is about the best undercoatings for lawn mowers. 

The best way to protect your lawn mower deck from rusting is to apply a graphite or silicone coating on the deck. Graphite will form a hard and slippery coating on your deck that will easily inhibit corrosion and rusting in the metal surfaces you apply it to. 

All it takes for rusting to happen is water and oxygen. This means the conditions of your lawn mower deck are ideal for rusting to take place. You should also know that clumps of grass and leaves underneath your lawn mower represent a fire hazard. And you should make efforts to remove debris on your deck from time to time. 

If your lawn mower deck is starting to rust, all is not lost. And if your deck is yet to start rusting, then steps can be taken to prevent rusting and protect the deck. Graphite is the best undercoating for lawn mower decks as discussed above and steps to apply the coatings will be explained in this article. 

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Safety is Paramount

Before you apply any coatings to your lawn mower deck, you should first remove the deck as per the instructions in the owner’s manual. There is no general method to remove decks from lawn mowers as each make and model is different. However, before you remove the deck, place it upside down on any surface that’s flat and level. 

If your mower using an electric mower, unplug it before removing the deck. If it’s the type that uses fuel, tilt the lawn mower on its side while making sure that the gas side tank is pointing upward. It’s also advisable to place bricks both at the front and the back of each wheel. The reason for this is to properly brace the lawn mower and prevent it from tipping over as you work to remove the deck. 

Clean and Smooth Surfaces Means Better Coatings

To make the coating stick well, it’s important that the surface of the deck is clean and smooth. This is easy to achieve as all you need to do is to apply a strong stream of water from a garden hose to the underside of the deck to wash it properly and remove all debris. 

Any stubborn debris remaining on the deck should be removed with a plastic scraper. It’s advisable to put on safety glasses when using a hose to protect your eyes.

If part of the deck has already rusted, use a wire brush to remove rust particles. Allow the deck to dry completely after cleaning/washing its surface. 

Applying the Graphite

It’s easy to apply graphite to the deck surface. You have the option of using aerosol graphite or use a can of paint-on graphite. Whichever one you use, you’ll still get the same result. 

If you are using aerosol graphite, make sure you shake the can vigorously for a couple of minutes (several minutes is better, haha) to ensure the contents of the can mix thoroughly. After you are done shaking the can, remove the can and then press the spray nozzle while directing it towards the surface you intend to coat in even, long, overlapping strokes.

Any surface you don’t intend to coat should be protected by a newspaper or any other material. Using aerosol graphite is generally more convenient and simpler. 

On the other hand, if you are using a paint of graphite, thoroughly shake the paint-on graphite can. After that, remove the lid (you can use a screwdriver) and use a paint stick to stir the paint. When you are done, dip your paintbrush inside the paint and apply it on the deck and the blades. Make sure you properly coat all the metallic parts as they are susceptible to corrosion. 

The first coating should be a thin coating and should be left for about 24 hours to dry. After this, apply a second coating and then allow it to dry for another 24 hours. After this, you can start using the lawn mower. 

Finish Care

Make sure to remove debris on the underside of the lawn mower after using it. A garden hose will easily remove all debris as earlier established. You’ll also discover that debris will come off the deck easily after applying the coating. 

Protecting Your Lawn Mower Deck

While the coating is a good way to protect your deck, there are other steps you can take to protect your deck from wear out and rust. Here they are:

Avoid mowing wet lawns: It’s advisable to mow your lawn when dry. Recent rain, as well as morning dew, make grass wet, clump together, and then stick to your mower. Note that grass still has a high degree of internal moisture for as long as a day or two after rain even though they may appear or feel dry. So whenever possible, mow your lawn when it is dry. 

Mow regularly: Longer grass clippings increase the tendency of the grass sticking to your mower. This makes it beneficial to mow regularly to reduce grass buildup and the tendency of the grass sticking to your mower deck. 

Run the mower at full throttle: Your lawn mower is designed to operate at full throttle. Using your mower at slower speeds leads to messier curs which greatly improves the chances of grass sticking to the deck as it’s difficult to eject grass clippings. 

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