Lawn mower washout port. How to Clean the Underside Deck of Your Lawn Mower

How to Clean the Underside Deck of Your Lawn Mower

David Beaulieu is a landscaping expert and plant photographer, with 20 years of experience.

It’s no surprise that there are many opinions on how often a lawn mower should be cleaned. This is largely a matter of personal preference—just as some people sweep and wash a kitchen floor daily, others may only do it weekly or even just monthly. The same holds true for outdoor lawn and garden tools. Some people with a robust neatness gene may prefer to clean lawn mowers and other garden tools thoroughly after every use, while others find no need to be quite so meticulous.

Even for people who routinely wipe down and brush off the top surfaces of a lawn mower, not everybody will turn the machine upside down and carefully clean off grass clippings and grime from the underside of the mower—the area known as the deck. Among those given to debating the issue, the question has three parts:

  • Is it necessary to clean the mower deck? If so, why?
  • If it is necessary, how often should I clean the mower deck?
  • And how exactly should I do it?
lawn, mower, washout, port

A related but different question has to do with what TLC you should give the lawn mower when you are ready to put it away for another year.

Yes, the Lawn Mower Deck Should Be Cleaned

The reason for cleaning the deck—the enclosed housing beneath the mower, where the blade spins— has nothing to do with being neat (unless you are the type who takes pride in showing guests your power equipment). Cleaning will actually help lawn mower performance by allowing the blades of grass to stand fully upright as the blade spins to trim them. A lawn mower deck heavily encrusted with dried grass clippings may deflect the grass blades so they can’t be cut efficiently, and in worse-case scenarios, the dried grass buildup can even hinder the rotation of the blade itself.

Keeping the bottom deck clean also helps minimize the spread of lawn diseases. Remember, when you cut blades of grass, you are essentially opening up wounds that make the grass susceptible to problems such as fungal disease, which may be lurking in the grass buildup on the bottom of the mower.

Do It at Least Twice Each Mowing Season

There is no rule about how often to clean your mower deck, but it really should be done at least twice each mowing season. You may need to do it more often if you’re forced to mow very long grass or if you have to mow it while it is wet.

It’s also wise to clean the deck of your mower at the end of the season, before putting the mower away for the winter. It’s unpleasant to leave grasses to rot and mold on the bottom of the mower over winter, especially if you are storing your mower in an attached garage or basement. Left to harden over winter, your spring cleaning chores will be all the harder.

How to Clean the Deck on a Lawn Mower

To clean the deck of a lawn mower, follow these steps:

  • Empty the gas tank (or run the mower until the tank is empty), then disconnect the spark plug wire.
  • Stand the mower up on its side.
  • Take a garden hose and spray the deck at full blast. This will loosen some of the dirt and caked-on grass clippings.
  • Scrub off the rest of the soil, using a brush, soap, and hot water.
  • Rinse, then dry the metal deck of your mower.

Tip: To reduce future incidences of grass clippings sticking to the lawn mower’s underside, lightly spray some vegetable oil onto the deck after cleaning it.

End-of-Season Maintenance

When the mowing season is over in the fall, empty the gas tank by allowing the lawnmower to run until its gas tank is empty. Leave the lawn mower’s tank empty until spring comes, if possible. When old gas lies around in the lawn mower all winter, it becomes gummy and may foul the engine. If you must leave the tank full of gas, add a can of fuel stabilizer to the mower tank, then run the engine for a few minutes to distribute the stabilizer through the fuel lines and engine cylinder before putting the mower away.

After dealing with the gas, drain the oil crankcase and refill it with fresh oil.

These steps should make your lawn mower ready to go when you pull it out of the garage or shed next spring. But if you do end up having trouble starting your lawn mower, it may be because you need to tune up your machine, which is a fairly easy DIY task.

How to use a water hose attachment on a lawnmower, step by step

A lawnmower keeps your garden beautiful and presentable. It is responsible for cutting tall grass, unnecessary weeds, and rough-looking patches. Proper maintenance is crucial in keeping the lawnmower working efficiently. One has to take care of the cleanliness of different parts too. Cleaning the mower’s blades and the deck is part of the maintenance you have to perform after finishing mowing. The advantage of using a hose attachment on a lawnmower is that you only clean the underside thoroughly, and the engine and other parts keep relatively dry. This blog post will take you through the steps to attach a water hose to your lawnmower. With it, you can clean your mower easily in a couple of minutes.

How to use a water hose attachment on a lawnmower, step by step:

  • Step 1: Prepare the mower
  • Step 2: Lower the mower deck
  • Step 3: Screw the hose attachment to your mower
  • Step 4: Let the engine run for a short while
  • Step 5: Disconnect the hose attachment and dry the deck
  • Step 6: If there is no hose attachment, how to clean the deck

Attaching the water hose itself is relatively simple. It only needs a few basic steps. But you have to be careful as you are exposing a mechanical device to water.

You might have noticed that many new lawnmower decks have a new hose connection point on them. For example, a Craftsman lawnmower’s hose attachment is part of the mower’s deck wash system. The benefits of cleaning the deck start as soon as you finish mowing. You might wonder how to use them, or they are effective, or what precautions you have to take when using them? This blog post tries to answer these questions.

General Guide:

While mowing, your mower blades get dirty. If the grass is slightly damp, clippings of grass get stuck together on the mower blades and underside. These clippings increase the chance of rusting, so it is better to clean them after mowing each time. A water hose attachment is the fastest way to solve the issue.

Step 1: Prepare the mower

Place the lawnmower on a smooth and level surface close to a water source with a hose. Leave transmission in gear and set the lawnmower to the parking brake so that it does not start rolling. Ensure that there is enough gas in the tank as you will have to turn the mower while the water is running. Make sure that all the moving parts have stopped when you start to work.

Step 2: Lower the mower deck

The next step is to find the water hose port on your lawnmower. It will most likely be present on top of the mower deck that contains the blades underneath. It is present in both push mowers and riding mowers. Now, lower the cutting deck to the lowest level. This step is needed for riding mowers. Push mowers have a fixed deck and need to reduce the cutting height to the lowest level.

Step 3: Screw the hose attachment to your mower

First, remove the grass bag if your mower has one. Now, inspect the water hose port you found earlier on the mower’s deck. Check the kind of connection you require, a push-in connector or a twisting type. For some models, you have to screw the attachment on the lawnmower deck. Check that the hose has the same connector that your mower requires. Attach the nozzle adapter on the deck washout port. Generally, it is better to use a lock collar to fix the adapter with the mower’s deck attachment. The lock collar releases the water flow when turned clockwise and stops the flow when turned the other way.

Now, open the tap and release the lock collar, letting the water flow. The nozzle connection should be tight. Always double-check the connection because it may come off and wet other parts if it is not tight enough. Especially, the mower’s engine, the battery, and some other electrical parts do not like water, so be careful.

Step 4: Let the engine run for a short while

After the water starts flowing through, you have to clean the blades thoroughly. To do this, start the engine and let it warm up. Then, engage the mower’s blades and let it run for at least two minutes. As the blades turn, they swirl the water in the deck gushing out the clippings and wiping the blades properly. If you have a riding mower, sit on the seat and move the throttle to the fast position. Run the engine until no more clippings flow down with the water from your mower’s deck.

Step 5: Disconnect the hose attachment and dry the deck

Now, stop the engine and turn off the water supply. Disconnect the hose attachment from your mower. Start your engine again and run it for a while to dry off the underside of the deck. Another way is to let your mower dry outside.

If you want to clean the top of your mower, you may use a leaf blower once your engine is cooled down but never use water from the hose to clean it.

Step 6: If there is no hose attachment, how to clean the deck?

The whole procedure is similar. Turn the faucet on and hold the other side of the water pipe opening in your hand. Aim from low to the ground up to the underside of the mower’s deck. That way, the water will hit the blades from the front or rear wheels. Keep a safe distance and spray the water in as the blades spin. This should do the job. You probably need two persons to do this, and the one that holds the hose will probably get quite wet.

Additional concerns:

Use of Pressure washer: Be careful using a pressure washer for cleaning the mower deck because it can force the water into your mower’s critical and sensitive parts. The engine, battery, and other electrical parts do not like water. Also, be careful not to wash away lubrication on various parts

Read the manufacturer’s manual: Always read your operator manual. If it says never use water to clean the deck, don’t try to use it even if you have the hose attachment. It is probably better to use an air pump for the same purpose.

Scrapping technique: Scrapping under the mower deck is another way of keeping things clean in the mower deck’s underside. You should also check the clippings cluster before you use the water. If you find any uncommon clogging or stuck branches, remove them before the operation.

Let the deck dry: Allow the underside of the mower deck to dry properly. You can use an air pump that circulates the air to let it dry faster. Also, never use a mower that has been recently washed to cut grass. Wet blades and deck will stick grass much more easily, and you will end up with the same dirty machine.

Frequently asked questions:

Why is there a hose attachment on my lawnmower?

If your lawnmower has a hose attachment, it is there as part of a deck wash system. It helps easily remove grass clippings, dirt, and other debris from under the mowing deck. It will help keep your mower’s components from clogging or jamming and ensure that the machine produces the best possible grass trim. You can clean sharp blades with zero physical contact with them.

Is it ok to wash the mower blades with water?

It is completely fine to use the hose attachment. Spraying the water beneath the mower’s deck comes as an additional feature. The mower blades can withstand moisture, branches, and dirt. So, it is perfectly ok to clean them with water. Avoid spraying water on other parts of the mower. And be very careful with using a pressure washer to clean your mower, as it can force the water into unwanted parts. It increases the chance of rusting, seizing, jamming, or problems with the battery or other electrical system parts.

What can I do if the water hose attachment is damaged?

If the water hose attachment is damaged, you can always get it repaired at your local dealer. You can also try to fix the broken tip at home with some adhesive or another method. If you use glue, ensure that you do not glue any other parts accidentally. If fixing is not possible, and as a final resort, you can hold the hose over the attachment hole as it is only a 2-minutes job. Also, look into the last step of the blog for an alternative method.

Final remarks:

Cleaning the underside of the deck is a job you should do after each mowing session. Regular cleaning of blades and cutting deck makes your machine last longer. Using a water hose attachment makes the job super-fast and easy. There are only a few additional precautions one should take. In this blog post, we have explained how to use the water hose attachment. Ensure you keep the water away from the engine and electrical components. Please do not use a pressure washer, as it often hurts more than it gives. In the last step, we have provided some directions on how to clean without a hose attachment.

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All power levels are stated gross horsepower at 3600 rpm per SAE J1940 as rated by Briggs Stratton.See operator’s manual or dealer for complete warranty details. Length of engine warranty coverage varies by manufacturer.†Suggested will vary by market. are shown in U.S. and Canadian dollars. Set-up, delivery, documentation and destination fees not included. See dealer for details. Features vary by model. We reserve the right to change specifications, features and pricing without notice.

What is the best way to clean a lawn mower deck?

Especially when it comes to removing the caked-up grass from the underside of the deck.

So, what is the best way to remove caked-on grass from your mower deck?

Is there a product or method that works best to get rid of the grass?

That’s exactly what we are going to get into today.

After all, removing caked-on grass from your lawn mowers deck is part of regular lawn mower maintenance.

Below you will find the INSIDER methods lawn care pros use to clean their mower decks.

How do you clean a lawn mower deck?

Well, a good place to start is using the leaf blower to remove the grass off of the top of the deck at the end of each day.

But that will only get you so far.

And if you want to prevent your lawn mower’s deck from rusting out or failing prematurely. You really need to remove the caked-on stuff on the bottom of the deck.

So how do you do that?

Getting to Your Mower Deck’s Underside

The first step to cleaning your lawn mower’s deck is to get access to it.

If you have a common residential riding mower, you can pull the deck off in about 10 minutes once you get the hang of it.

And if you have a flip-up deck, you don’t have much to figure out.

On the other hand, if you are trying to clean a commercial mower. Getting to the underside of your deck SAFELY can be a challenge, and may require a bit of innovation.

You could build a ramp like the one pictured above, or you could purchase a jack to help you get to the underside of your deck.

Using a Scraper to Clean Your Mower Deck

Here’s the deal, when it comes to the underside, most lawn care professionals simply scrape their mower decks.

That’s it, that’s the BIG SECRET.

And they typically don’t use any product when it comes to removing caked-on grass from the underside of the deck.

So when it comes to cleaning the underside of your lawn mower deck, you may just have to get your hands dirty.

You can use several tools to scrape your mower deck including a:

However, it may be a good idea to treat the deck after you clean it to prevent grass from caking on the next time. To learn more on that keep reading.

What is the best product to clean a mower deck with?

When it comes to cleaning the rest of the mower. Including the top of the deck, what product should you use?

According to our research, the resounding answer for the best product to clean your mower deck with is Purple Power. Which is a commonly available degreaser.

41% of lawn care pros reported purple power as being their favorite deck cleaning product.

Further, we found that Simple Green was a close second taking in 31% of the vote.

Finally, the 3rd product recommended by lawn care professionals when it comes to cleaning a lawn mower deck was Ballard’s Mower Magic which snatched up 7% of the vote.

Using A Mower Deck Washout Port On A John Deere Garden Tractor. Same for Husqvarna, Cub Cadet, Toro

Ballard’s products are not as commonly available as its competitors are, so they can be harder to get a hold of. And many lawn care pros simply have not gotten to try the product, but they work great.

Good news! If you want to give it a try we have partnered with Ballard to get you exclusive deals. Not only do they sell great mower cleaning products, but they also offer a great lawn mower deck scraper.

One of the many benefits of being a GreenPal Vendor is access to exclusive deals!

“Just use a pressure washer”

20% of the lawn care pros that responded to our poll suggested that they don’t use ANY cleaning product. But simply use a pressure washer to clean their lawn mower.

While others reported using one of the products mentioned above along with a pressure washer.

Either way, a pressure washer is a much better way to clean your mower and mower deck than a garden hose.

Whether or not you use a product.

How often should I clean my lawn mower deck?

This is crazy but some lawn care pros find they NEVER have an issue with caked-on grass.

While others need to clean their lawn mower decks 2-3 times a week.

So really, how often you clean your lawn mower deck will depend on how often the need arises.

For example, lawn care pros that cut lawns in sandy areas find that the deck tends to clean itself.

The most common answer lawn care pros give is that they scrape the deck each time they sharpen their lawn mower blades.

And as we have covered in other articles, 75% of lawn care pros sharpen their blades at least once a week.

lawn, mower, washout, port

Ideally, you want to scrape your lawn mower deck before any caked-on grass has time to dry.

Due to the varying conditions you may experience, the answer to how often you need to clean your lawn mower deck can vary from after every lawn, to never.

Treating your Mower Deck After Scraping

Once you have scraped your lawn mower’s underside, some suggest that it’s a good idea to treat the deck with a product to prevent caking next time.

Simply using a product like WD-40, or even Pam can prevent grass from caking on your lawn mower deck in between cleaning.

That’s really all there is to it, scrape your deck, and wash with a product if you choose to.

And once the deck is dry, treat the underside with a quick spray to prevent buildup down the road.

Cleaning Your Lawn Mower’s Deck at the End of the Day

When it comes to cleaning the top of your lawn mower’s deck and underside. You will need more than a little bit of toilet paper.

Here’s the secret, most lawn care pros find that simply scraping the deck is more than enough to maintain their lawn care equipment.

But when you do wash the rest of your mower you may want to consider a product like Simple Green, Ballards, or Purple Power to really make your equipment shine.

Finally, don’t forget to post-treat the deck with a product like WD-40 to prevent build-up on the underside down the road.

Looking for more to read? Check out our guide to starting a lawn care company.