Wash Down Pump System

Published date: September 5, 2017
  • Boat Type: Boat Type

My slip is in a marina that does not provide water. Since it is a lake with relatively clean water, most folks at the marina do the old shool bucket method to wash their boats. That gets old really quick, and I wanted something better.

After searching the mods posted by my fellow Mac owners the following mod posted by Gazmn appealed to me because his system was able to pump water from his tank, or with a hose tossed off the transom, pump from the sea (or lake in my case):

I purchased the same Wash Down Pump Kit as Gazmn off of Amazon:

I also got some ideas from the following two mods:
Mark Chamberlain
Tahoe Jack.

The most helpful article that I found on the web was this one:
Installing A Deckwash Pump
By Don Casey

Keep in mind I already had a Flexible water tank and 12V pump & faucet:
By adding a TEE in my existing water line and attaching a new hose from the tee to the bulkhead fitting I installed under the helm seat, I was able to pump water from my Flexible Water Tank using my new Wash Down Pump. I did add a "Check Valve" per Don Casey's instructions to keep pressure in the system, and prevent lake water from entering my Flexible Water Tank. To pump from the lake I use one of the hose connectors that was provided with the kit to attach a 3/4" inside diameter hose with a strainer on the end that I toss off the transom to get an infinite supply of water. It takes me about 30 seconds to switch between the tank and sea water hoses on the Johnson pump. The pump has really good pressure (5.2 GPM). It will shoot water about 30'. I was very careful to keep all water connections leak free in order to keep pressure in the system. If you do this the pump will only turn on when you squeeze the handle on the spray pistol. There is a little knob on the spray pistol that will allow you to keep the water flowing after you release the trigger in case you want to take a redneck shower in the cockpit.

My original plan was to mount the pump in the bilge area of the rear berth and use two bulkhead fittings, one input and one output, but could not come up with a good method to switch between the tank or sea water. After pontificating over a cold brewski I decided that in this case simple is better because of the quick connect fittings on the Johnson pump. So, I simply mounted the pump under the helm seat for easy access.

I used 10-gauge wire, and made all wire-to-wire connections with crimp butt connectors, waterproofed with adhesive-lined heat shrink tubing. I used a heat gun for the heat shrink. I even went the extra mile and covered the heat shrink connectors with liquid tape.

Since I did not want to drill a huge hole through two layers of fiberglass to mount the switch under the helm seat by the pump, I mounted it in the cabin, in front of the battery compartment. I am able to reach the switch from the cockpit with my long arms.

In summary, all three of the wash down pump mods that I found on www.macgregorsailors.com were for the 26X. The 26M is different, and requires a different solution.

This also inspired the following revelation.

Brian's Law: The cleaner the boat, the more bird poop it attracts.

Published by: Brian

Model Year: 2006
Photo Caption: Pump


sea water hose


Useful information

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