SJ23 Tech Tip E19, (Updated 2023-03-18) Bob Schimmel (UNDER CONSTRUCTION)


Deck Wash Pumps - Portable & Permanent Mount.
INDEX - Uses, / Portable Pump, Parts / Permanent Pump, Parts.

It is incredible how well rain water can clean a deck, or anything else for that matter.  Most people don't wander around in the rain so they don't see this.  Morning dew has a similar property and again, most people get out of bed after it evaporates.  Next time, go on deck right after a heavy down pour to see how clean it is.  That pristine surface demonstrates the cleaning power of rainwater.  I'm not about to suggest you stand out in the rain with a deck brush, but if you get up a little earlier, you can clean the deck with the morning dew.  There is a dust particle inside each rain drop that needs to be cleaned.  A past sailing buddy used to preach this philosophy to me all the time.  His deck was bone dry by the time anyone even thought about waking.  He drove me nuts with this but had the cleanest boat in the club and he made good coffee in the morning!

PUMP USES - For years I used a bucket of lake water and a brush to wash Panache's cockpit and deck.  A bucket is OK but frankly the swoosh doesn't wash debris away very well.  A brush without flowing water is wanting to remove grunge from a tight space.  A steady stream of water from a hose, on the other hand, can be directed into that space to force debris out and float it away to where it flows overboard.  Nice to have endless water.  A deck wash pump is also quick and easy to clean a spill or remove foot prints from dirty shore based shoes.  It can easily fill my solar water heater for a cockpit shower or the flush tank of the portable head.  What decadence.  For an emergency the portable pump could backup an existing bilge pump or remove water from a cavity not serviced by a bilge pump (eg: cabin or under the forward berth).  It can also be used to remove water from an adjacent boat.  You get the idea, but lets not overrate this little pump.  And lastly it is a great way to wash an anchor lifted from a muddy bottom. 
I expect the pump will be used most of the time near the cockpit, in which case it will be hung over the side from a primary winch.  If I'm cleaning the cabin top or foredeck it will likely be hung from the centrally mounted spring cleat.

PORTABLE DECK WASH PUMP - To create pressure water on board hang this 12V centrifugal pump over the gunwale hung inside a 4' length of ABS pipe.  (In my fabrication I joined a 4' long 1.5" ABS pipe to an 8" long 2" pipe to use garage stock but a single 4' long 2" ABS pipe is probably simpler).  Using ABS pipe is perfect to keep the pump submerged and to protect it when the assembly is stored in the cockpit locker.  I chose a pump that is identical to those installed under the settees; serving as a spare that is known to work.  (See Tech Tip E16). 

- The electrical wires, vinyl hose and gunwale tie down line all exit at the top of the ABS pipe.  It takes a bit of clever thinking to fish the wires and vinyl tube down ABS and secure the pump inside, near the bottom, all the while keeping the vinyl tube attached to the pump.  I'll let you figure out that part but note the white tie wraps holding the pump inside the 2" section.  In reality it's too wordy to describe, but not that difficult to do.  You should also secure the wire, vinyl tube and tie down line at the top of the ABS pipe so you don't accidentally pull them off the pump.  The electrical plug draws power from the 12V jack on the breaker panel and the switch is located along the cord where it hangs just in the cockpit.  Its convenient to operate here and doesn't get beat up due to the cleaning task at hand. 
- A centrifugal pump can move more water in the forward direction than in the reverse direction.  The DC motor can turn in either direction and the positive lead is usually labelled.  If the power is applied to the motor so the pump operates in the forward direction you will see the stream going furthest out the nozzle.  This is the correct polarity to operate the pump, regardless of the lead labelling.  I found one pump to be labelled backwards!

This pump has a lift capacity of ~10' so it has sufficient force to do reasonable work.  The end of the tube might get a nozzle to create a more forceful stream of water but the biggest advantage is a steady flow of water. 

This pump is stored in the cockpit port locker with the wires and hose secured to the tube using a Velcro strap.  Later I may house it all in a nylon bag.  Another thru hull installation adverted.

The first time I used the pump to clean the cockpit I was surprised with how well it worked.  Moving water is everything after all.  In half an hour I washed all the debris from the toe rails, under the mainsheet traveller, cockpit seat lids and the cockpit sole.  All winter debris that has a nasty habit of sticking around for the summer.  Its a great tool for emptying a dinghy filled with rain. 


  • 4' of 2" ABS pipe.

  • 1 Self priming bilge pump; CK-181DC, rated at 200 gal/hr, 1/37 HP, 12V, carbon brush motor, polypropylene impeller.  (See Tech Tip E16 for photo)
    - Tested to empty a 23L bucket in 1 min. & measured head of ~10'.

  • 15' of 1/2" vinyl tube.

  • 15' of lamp cord.

  • 1 12V accessory plug.

  • 1 lamp cord switch.   TOP

UPDATED  PERMANENT MOUNT DECK WASH PUMP - It is difficult to keep a boat on the prairies clean, given the dust blowing off the fields.  Locally we have coal dust from two adjacent open pit mines.  Some sailors manage to keep their boat spotless.  They are hugely anal about it but I never let on that I'm still envious.  Frankly, I have other things to do, so what I need is a quick, efficient deck wash pump with good cleaning power.  To this end there is nothing like a purpose made pump that can push lots of water.  If you combine high pressure with a convenient quick connect coil hose it becomes a convenient tool I'm apt to use often.  Come to think of it, this pump will come in real handy to fend off marauding "pirates" on the lake.

In Panache's installation, the pump will be installed on a purpose made wood shelf, under the port settee.  The shelf will be glued to the hull with Sikkens Sikaflex.  The pump inlet will be connected to the vacant thru-hull fitting.  Since the thru-hull is underwater the displacement pump will automatically be primed to protect the rubber impeller from a dry start.  However, the thru-hull valve will normally be closed between uses, for all the obvious safety reasons.  The pump outlet will be plumbed through the aft settee bulkhead, go through the port locker to an RV "exterior spray port" installed through the aft cockpit wall under the tiller.  There is ample space here for it. 

A 12V pump that produces household pressure typically draws a lot of current.  The one on Panache draws 10A.  For this reason it will be connected to BKR 9, the 15A cabin breaker, and will bypass the load shunt due to the high start up surge current.  The wiring will be #10 AWG stranded.  The power switch may be installed next to the spray port for convenience while connecting the hose.  The alternative is wireless control that has the advantage of saving the impeller and power when the nozzle is closed.  An impeller always needs to be cooled and lubricated with water.  This pump will see occasional short term use so the 10A draw won't be a problem for the charging system or the battery.  In fact the high short charge current may be beneficial (acting like a quick equalize charge) if the pump is used with the battery charged. 

Operationally any spilled water from the spray port will flow to the cockpit drains.  The spring loaded check valve in the spray port is normally closed until a hose is plugged in.  However, I'm not counting on it working all the time so I'm installing it above the water line.  The last thing I need is a hardware leak to fill the hull.  Hence the practice of closing the thru-hull between uses.  A 15' long vinyl coil hose connects to the quick connect fitting of the spray port.  The coil hose or an expandable hose are both self draining, kink & tangle resistant and take up little storage space (8x12)".  The soft outside is easy on the gel coat and weighs far less than a typical garden hose.  All useful features in the tight storage spaces on an SJ23.


The pump is to be installed on a shelf under the settee.  This is just below the thru-hull so it can prime the impeller when open.  I'll have to remove the hoses to drain it dry for winter.  I'm considering a wireless remote control for the motor to eliminate a cockpit switch & save walking to the cockpit.

The outlet hose will go through the aft settee bulkhead at the top left corner.  After that the hose goes through the starboard locker to the spray port.


I get interesting the opinions when talking to local sailors about this deck wash pump.  All like the idea of an easy cleaning method BUT hate the coil hose.  Others hate the collapsible hose.  So a field trial is in order.

An exterior RV spray port will be installed in the aft end of the cockpit under the tiller.  This spot is clear of other devices.  A potential leak will go out the cockpit drains below the spray port.

Coil hose e/w mating connector to spray port fitting.


So far this pump and coil hose combination produce sufficient flow, similar to a garden hose.  Given that the coil hose can stretch to 10' I can comfortably clean the cockpit, which is usually the dirtiest, and the cabin roof, next dirtiest.  The spray can easily reach the foredeck.  The force will be sufficient to push the dirt off the fore deck if I stretch the hose to the mast.

  • Installed spray port under the tiller.  (Not yet)

  • Installed pump.  (Not yet)

Pump in operation.  (Not yet)  


  • A wood shelf (10 x 4.5)" in the settee to mount the pump on.

  • A short hose e/w adapters to plumb the thru-hull to the pump. 

  • 12V mini pump e/w garden hose connectors, 230 gal/hr. 

  • Suitable length of 1/2" garden hose e/w adapters to plumb the pump to the spray port.

  • Right angle adapters to connect garden hose to spray port.

  • RV exterior spray port hook-up e/w quick connect coupler.

  • 15' coil hose e/w a quick connect coupler and sprayer.

  • Electrical wiring (10 AWG) to power pump.

  • Electrical switch (15A) to operate pump.

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