31 Gal Flex Tank, Water System W/ Transom Washdown / Shower

Published date: June 11, 2007
  • Boat Type: Boat Type

Water system:
This water system plumbs lines to the head, transom [outside] &
the galley. It'll provide 31 gals of freshwater to all outlets. By
adding the raw water inlet, @ the transom, on a 3/4" garden
hose Y valve with shutoffs, you have a fresh or raw water
washdown / transom shower on deck; And an unlimited water
supply for the boat.

Parts include but not limited to:

31 gal Plastimo flexible tank
Johnson washdown pump system
2 Brass Y valves W/ shutoffs [Loews Gardening or Home Depot]
Preferably with metal shutoffs

1. Temporarily remove styrofoam from upper bow area. Decide
placement of water inlet. I chose the black stripe on starboard
side, near the front hatch opening.[Pic 1] Seal and screw in
fixture; run water inlet line through to very front.
2. Drill hole through upper bow box at very front.
3. Drill or widen current opening [access panel in V berth] to the
bow floor. Hose will show a short distance
4. Remove foam from lower V berth for flexible tank. Install
5. Make a hand sized cutout in the middle of the V berth
forward cover. When work is completed you'll reach between the
v berth mattresses and check level of the flexible tank by feel
here.[pic 2] note water inlet hose showing in front & Dri deck
cover for air circulation under mattresses.
6. I tried to place moved foam in other boat areas.
7. Drill hole through fiber glassed wall that separates front foam
compartment. Run water out line through next available
compartment. I chose the port side opening and added a water
filter and shutoff. [Fresh output 1]
8. I used 1/2" poly hose with 3/8" ID, from Home Depot for all
runs after the shutoffs. Run line from shutoff down starboard
bilge through to transom. Because the hose is so small you can
feed it through your large cable through 2X.
9. Feed "Fresh output 1" through transom hole route to the A
side of 1 brass Y valve which we'll use as a 2 feed input valve.
The B side of the Y valve will be used later as a raw water inlet.
By connecting a short hose that can be dropped into the water
or a bucket, later.
10. Using short appropriate diam hose connect the Y stem to the
filter of the Johnson washdown system. I chose to make this
filter accessable to the rear transom to keep an eye on it, which
required some improvisation of the system parts.
11. Feed line from valve stem back through transom opening,
and into the Johnson Pump In. I stationed the pump inside,
under the cockpit at the rear wall of the aft berth. You want to
keep the raw water suction run to less than 5'. You accomplish
the same with the 26' freshwater line by priming its line.
12. Connect 2nd Y valve to the pump out. This #2 valve will run
the A output to your transom washdown hose. This output will
require it's own opening in your rear transom with either a quick
connect or male garden hose out. This will be housed on your
transom and is covered by other mods ie: [url= http://
action=view&record=783] Jack's Washdown [/url] and [url=
action=view&record=526] Mark Chamberlan's [/url]
were my inspirations. I chose a straight handle multi tip garden
nozzle whose dial includes: misting, jet, flat, spray shower etc.
13. The B output is split to supply the galley and the head. Use
any faucets you'd like. I used those I had on hand. [Pic 3]
14. I tend to leave both outputs of this #2 Y valve in the open
15. Seal all connections and clamps with compression tape, so
they remain water and air tight.

Regarding the #1 Y valve. I leave the raw water inlet [formerly
called B side] closed until needed. However, this input can also
be used to fill the freshwater bag by connecting a garden hose
at the transom with a double female 3/4 garden connection. BE

Happy Boating

Published by: Gazmn

Model Year: 2007


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