Mower Deck Spray Washer




Introduction: Mower Deck Spray Washer

I clean grass clippings from the underside of my 500-pound mower's deck with a sprayer I made from garden hose fittings. Not removing the clippings reduces the mower's efficiency and promotes rust, but it is difficult to reach under the deck or lift the front of the machine for cleaning. The sprayer alone does not have enough power to do the cleaning, but the whirling blades do. SAFETY RATING: This project has been awarded the grade of W by the League of Crackpot Scientists, which stands for "What could possibly go wrong?" STATEMENT OF LIABILITY: If you or anyone else is injured or any property is damaged during the construction or use of the device described herein, it is all your fault. To see my related Instructables, click on "unclesam" just below the title above or in the INFO box to the right. On the new page that appears, repeatedly click "NEXT" to see all of them.

Step 1: Tools and Materials

Adjustable wrench, combination pliers, screwdriver, sharp knife, drill and bits
Several feet of five-eighths inch garden hose
Lawn sprinkler nozzles or heads suitable for mounting securely onto a board
Metal fittings for five-eighths inch hose, and washers
Wood or plywood for frame or base
Sheet metal screws

Step 2: Layout

The shape and size of the sprayer base depends on the mower. My mower has three blades, and I wanted a sprinkler head below each of the blade hubs. My frame is a short length of two-by-four wood joined to the middle of a longer one using pocket screws. The spacings of the blade hubs were marked on the frame for locating the sprinkler heads.

Step 3: Assemble the Hardware

I chose low-profile sprayer heads, drilled two quarter-inch diameter holes in each, mounted them on the frame using large sheet metal screws. I then determined what hose fittings I would need to be able to supply the three heads from one inlet connection to my garden hose

Step 4: Connect the Hoses

The hose fittings were tightened in place and lengths of garden hose cut to run between them. Hose clamps are usually included with the fittings.

Step 5: Kinky!

A short run of hose did not conform to the required shape without kinking, so water could not flow through it.

Step 6: Ticketyboo

Adding angled fittings allows the short hose to be a straight run.

Step 7: Let Us Spray

First test of the sprayer. The Great Yellow Beast looks on, feigning disinterest.

Step 8: Blowing Chunks

The lower edge and blades of my mower deck are low enough to the ground, even in the highest position, that the machine must be elevated above the spray washer. I park the mower on a set of open-work metal loading ramps with the sprayer underneath. To be most effective, the cleaning should take place following each mowing, but most importantly immediately after mowing high and/or wet grass. With the water flowing and the blades spinning, the underside quickly gets a good wash, even though I use standard blades, not the optional high-lift blades. This method may not remove a thick longtime accretion of dried clippings from a mower deck, so they might need to be removed mechanically before the spray cleaner is put to use for the first time. Running the blades again after the sprayer is shut off blows any remaining water from the underside of the deck.

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    4 Discussions


    7 years ago on Introduction

    Thanks for the pictures. How is this holding up? Have you had any issues with rust or your spindles?


    9 years ago on Step 6

    Instead of buying another expensive fitting you could have rotated the sprinkler head. Drilled the holes closer on the sprinkler or put two in one side to hold it. Nice washer though, I have been thinking of building something to wash my mower.


    9 years ago on Introduction

    I've seen newer mowers with a hose connection on the mowing deck for just this purpose. This is a nice and easy alternative for those of us who don't want to pay to upgrade just for that feature. You could also possibly make it out of PVC with either drilled holes or some sort of sprinkler head fittings that might be lower to the ground, without having to elevate the mower on a track.


    Reply 9 years ago on Introduction

    Webman, if the manufacturer of my mower had offered a cleanout fitting, I probably would have bought that option. After reading reviews and complaints on the Internet, however, I found that many people were not satisfied with the built-in or add-on cleaners. The water outlets intended to spray water under the deck get clogged and covered by the grass clippings, so the cleaner is not effective, is more trouble than it is worth. Your idea of making a spray washer out of PVC, even with just drilled holes, will certainly work if the water supply has sufficient pressure. A Google search of "mower deck washer" produced a YouTube video if a similar device in operation. It would be easier to build than mine. However, I was worried about the washer rising up into the spinning blades, so went with the heavy-ish base, even though I then had to elevate the mower over it. I worried that water pressure operating on the supply hose and suction from the blades might cause the sprayer to creep up and hit the blades. One built along the lines you suggest could be staked to the ground using large wire landscaping staples sold at home centers. U.S.