How To Keep Grass From Clogging A Lawnmower Deck

Although almost every household has a mower, many owners don’t clean their machines as well as they should. One of the most prevalent (and easily preventable) problems is grass buildup on the cutting deck. As the blades work, they will spit grass and mud in all directions, which collects on the metal covering. Over time, this buildup can cause various problems and may even force you to replace your lawnmower.

The best way to prevent grass from clogging your mower deck is to wash it off after every session. If you have a riding lawnmower, doing this is much easier, thanks to the wash port that comes on all new models. For push mowers, you will have to turn the machine on its side to scrub the cutting deck. Afterward, you want to place some kind of sealant, such as nonstick cooking spray or Teflon. Doing this will keep most of the grass from collecting next time.


Why Grass Buildup is Bad For Your Mower

The primary reason why so many lawnmower owners don’t clean out their cutting deck is that it can be kind of a pain to do. Again, if you have a riding lawnmower, there is really no excuse to keep it clean as long as you have a standard garden hose.

However, even with a push mower, cleaning the deck is much easier when you do it often. Here are some problems that can happen when grass starts clogging the machine.

Rusted Parts – Even if you’re in a hot and dry climate, grass blades retain water. As the grass builds on the mower, it will cause rust. In extreme cases, the metal may rot away entirely, leaving holes in your cutting deck. If that happens, you’ll have to replace it, which can be expensive.

Loss of Suction – If you want your lawnmower to work efficiently, you need to keep grass from clogging it. Once you notice that your bag isn’t getting filled as much or it’s taking longer to mow your yard, that is a sure sign of grass buildup.

Worn Engine – If the grass is clogging the cutting deck, that means your mower has to work extra hard to keep cutting. This stress can wear out the engine and force you to buy a new machine within a few years.


How to Prevent Grass From Collecting on Your Mower Deck

1)Inspect the Cutting Deck

Depending on the type of mower you have, inspecting the cutting deck may be easy or relatively challenging. We’ll outline the steps for both push and riding lawnmowers below.

For Push Mowers

Be sure to keep the gas and oil tanks on the upper side of the lawnmower when tilting it. You will also have to prop the machine up so that it doesn’t fall back down while you’re working. For the best results, we recommend emptying the gas tank beforehand, if possible.

For Riding Mowers

The first time you remove the cutting deck can be tricky, but once you’ve done it, the process is relatively straightforward. Each model has a similar layout, but you’ll want to check your owner’s manual before proceeding. Typically, you have to lower the deck all the way, then remove the connectors that hold the deck to the arms. You will also have to remove the drive belts that spin the blades.

We recommend placing the deck on wooden blocks to relieve the tension and allow you to work faster. Riding mower cutting decks are usually pretty heavy, so you might need an assistant for this job.

2)Scrape Off Grass Buildup

Unless your lawnmower is brand new, chances are that some grass and mud have collected on the underside. If your mower has been sitting for years, the buildup could be considerable. Fortunately, you can use various tools to scrape most of the gunk off of the cutting deck. A screwdriver or paint scraper can work well, although it depends on the hardness of the debris.

In extreme cases, you may have to soften the grass and dirt by spraying it with a detergent or solvent first, then letting it sit for about an hour.

3)Wash and Rinse the Cutting Deck

Once the big pieces are off, you can use a towel or dish sponge to scrub your deck clean. Ideally, you should be able to see the metal all the way around the blades. If there are a few clippings here and there, they won’t make much of a difference, so you don’t have to get the deck spotless.

If you have a riding lawnmower, washing the cutting deck is really easy. You will have to reattach the deck and run the mower for a few minutes, so park it in an area where waste runoff won’t be an issue (i.e., the driveway).

Follow the steps below:

a.Locate Your Wash Port – This is a small connector on the deck’s top side.

b.Connect Your Garden Hose – You will need an adapter to keep the hose on the wash port, but this piece is easy to find. Best of all, lawnmower manufacturers use the same dimensions, so you don’t have to buy a proprietary connector.

c.Lower Your Cutting Deck – Put it in the lowest setting possible. This will help keep the water inside and allow it to clean more efficiently. If you have a mulch port on the deck, be sure to plug that first before cleaning.

d.Turn on the Water and the Mower – The wash port only works if the blades are running, since they will disperse the water. You will have to sit in the seat to start the engine, and you’ll have to stay in it for about five minutes.

e.Turn Off the Water and Mower – If your cutting deck is really dirty, it might take a few extra minutes to get everything off. If you’re unsure, extend the time to be safe.

4)Apply a Lubricant

Since washing a riding mower cutting deck is easy, you may decide to skip this step. However, if you mow often and want to conserve water, applying a lubricant can enable you to go longer between cleanings. You will have to remove the deck again to do this step.

There are several options available, so pick the one that fits best for your needs. As a rule, the more often you mow, the more resilient your cleaning products should be.

  • Nonstick Cooking Spray – This is the simplest option since you likely have this spray in your kitchen. However, it does wear off quickly, so keep that in mind.
  • Teflon or Silicone – These products are ideal for preventing grass from clogging your mower deck since they can stick to metal for much longer. However, Teflon and silicone sprays are more expensive, and they can leach chemicals into your grass. In some cases, you might notice small brown spots pop up here and there.
  • Rust Protector – While this product won’t work as well as a nonstick coating, it does help prevent grass from rusting the metal.

Other Ways to Keep Grass From Clumping

While a lubricant can be effective, you can also try these tactics to keep your cutting deck clean.

  • Mow More Frequently – Longer grass blades will clump easier, so mowing often can limit clogging.
  • Avoid Mowing When the Grass is Wet – Wet clippings will clump almost immediately, so wait until the driest part of the day to mow whenever possible.
  • Run Your Mower at Full Throttle – If your mower is running at a slower speed, the grass will spread out more. Running the machine at full throttle helps alleviate this problem.
  • Switch to a High-Lift Blade – These blades accelerate the clippings better so that more of them will wind up in your grass catcher (or back onto the lawn).

Related Questions

How often should I clean my cutting deck?

Ideally, after every mowing session. However, as long as you do it once or twice a season (particularly before putting the mower away for winter), that should be enough.