Index

Cockpit Manual Bilge Pump - Installation Considerations.

INDEX - Winter Prep, Location Considerations, Wiring, Manual Cockpit Pump, Knotmeter.

Positioning a single bilge pump in a SJ23 usually triggers a long discussion of the pros and cons of various locations.  With a deep bilge this would be a simple issue to resolve but since the bottom of the hull is fairly flat and sectionalized into five compartments; (stern, main cabin, two settees and the bow) you have the dilemma of where to install a single pump.  In addition, there are no limber holes to let water flow to the lowest point.  For those of you who would install only one pump, Murphy's Law will catch up to you!  If you install the pump in the stern IT WILL LEAK in the bow.  Well you know the rest! 

In the spring of 2000 I had the "joyous experience" of having 10" of water inside Panache due to a "slight error in judgment" at launch time.  Panache was sinking perfectly level at the dock.  I wasn't "level headed" at the time, but that was a different matter.  The bottom line is that Panache took about 10 minutes to fill to this depth.  A lot of owners at the time speculated on how an SJ23 hull would sink.  So now you know.  A quick dive to the knot meter confirmed I forgot to install the knotmeter impellor; which I immediately rectified.  See Safety Note.  Then I started bailing with my 5 gallon bucket.  It's incredible how fast you can fling water when the adrenalin is pumping!  No harm done and besides it cleaned the innards quite nicely.  I wouldn't recommend this technique of "cleaning the bilge" to anyone but it sure did a marvellous job.  All kinds of things came floating out of those dark unreachable cavities.  A bystander asked me what I was doing, so I told him I was performing a Y2K test on the hull and he actually believed me!  Note to tourists, ask a dumb question and you will get a dumb answer!  I should also add that we took off sailing after the cabin was wiped dry but I noticed the boat handled quite poorly.  While underway we heard water sloshing and upon further investigation I discovered the settees to be full of water.  Oh oh, not good!  Then the next big question, "do we have another leak or is this water from the original incident?"  I quickly surmised that we weren't sinking and that I forgot to drain the settees.  Like I have all the experience in the world with a sinking boat!  I guesstimated that we had about 300 pounds of moving ballast.  Again, a great way of cleaning the bilge but not the recommended technique!  I dried the boat the next day and have not noticed any damage in the following years.  She sure sailed upright with settees full of heavy water though! 

• NOTE 1 - As a rule of thumb a 1" hole 5' below the waterline will flow at 44 gallons/minute.  The Rule 3700 bilge pump can just about keep up to this flow rate; until the battery runs out!  So run the engine generator to keep the pump running.

• NOTE 2 - An issue I discovered while bailing is that the two crew standing in the cockpit effectively stopped the cockpit from draining.  I thought that the water would flow out the cockpit drains but their weight, pushing the aft end down, was enough to prevent the water from flowing out.  (drain holes were still under the hull).  Additional water dumped in the cockpit only made the angle worse.  As soon as they stepped on the dock, the cockpit sole rose above the water line and it drained very quickly.  In open water I suggest the "idle" crew walk to the mid section or higher end of the hull.  This is the reason why the pump discharge must be overboard and as high as the bottom of the tiller notch.

Potential leaks in a SJ23 hull are the cockpit drain hose fittings, rudder gudgeon bolts, sink through hull fitting, knot meter, to a lesser degree the anchor locker drain, and deck leaks.  With regard to a SJ23 sinking, keep the following ideas in mind: 

• A boat that starts leaking in the bow will usually start sinking in the bow, Titanic fashion.  Ditto for the stern.

• A boat that has water sloshing around in it, is very unstable and can easily roll or capsize in waves that it could otherwise handle.  Many vehicle ferries have sunk due to their open interior construction.  Add some baffles to the inside and you greatly improve the odds of surviving. 

• There is no bilge under the cabin floor to collect water from all the compartments.  This "void" below the floor is filled with closed cell foam (does not absorb water) at the time of manufacture to bond the liner to the hull, resulting in a sandwich construction that adds considerable strength and stiffness.  However, I learned from Gene that some SJ23s had a small void above the keel, right behind the pedestal.  The void was the result of how the ballast (lead pellets) settled.  I discovered a void on Panache and filled it with about a cup of liquid epoxy poured through a tiny hole I drilled in the sole.  This ended the flex of the floor where the center board lift cable is attached.

• I've owned Panache since 1985 and there was water in the hull only once when I forgot to install the knot meter prior to launch.  Other than that, the water came through a deck leak or open companionway.  Despite this I'm installing 3 electric bilge pumps and maybe a manual pump similar to Bret's below.  I was given 2 pumps, so bought a third, as I couldn't resist the chance of dealing with nuisance water, automatically.
  - IN PORT LOCKER: An automatic 800 G/H centrifugal pump e/w internal float switch.  (12V, 5A, 3/4" discharge hose is supported in a wood channel, through the port transom level with the bottom of the tiller slot).
  - IN EACH SETTEE: A manual 200 G/H centrifugal pump e/w external float switch.  (12V, 1.7A, 3/8" discharge hose supported in a wood channel, through to the top of the cockpit wall).  It is relatively easy to run tubing to the cockpit.
  - PORTABLE: A manual Victory 12-25 G/M diaphragm pump.  (1" discharge hose).

WINTER PREPARATION - Its not unusual to have nuisance water in the bilge compartments from rain, deck leaks, knot meter extractions, water tank, etc.  But once the boat is on the trailer all of it must be wiped dry for winter freeze.  My experience is that what little water is left evaporates quite quickly if the bow, stern and settee compartments are left open at least a week prior to freeze up.  Once the boat is bone dry it can survive winter freezing quite nicely.  I passively vent these areas to promote drying prior to winter but sometimes Jack Frost arrives sooner than expected, in which case I'm wiping up slush.  It demonstrates another reason for having bilge pumps to keep the bilges dry during the season.  See Tech Tip A11. 

The following are some general thoughts to consider for a bilge pump. 

1. The pickup hose and strum box must be as low as possible in the bilge. 
2. Secure the pump and float switch to the bilge with a high quality marine adhesive or a clamp so it can't tip or move.
3. Protect a pump and float switch with a blocking wall or screen that allows water to pass through.  Keep your stored gear from sliding to a pump.  You don't want to shear a hose off or block water flow.  This is particularly important for the flat bottom settees of an SJ23.
   - Use a large diameter screen for the strum box to prevent plugging the pump. 
   - Size the screen so the pump can move water at full capacity with the screen half restricted.
   - Keep in mind that debris will float around and be drawn to the pickup tube. 
4. Use non-collapsing hose for the pickup tube that matches the size of the pump.  Same size in and same size out.  NEVER reduce the size. 
5. Install the SJ23 port cockpit locker discharge fitting on the port side of the transom at about the same height at the tiller notch in the transom.  There is no point going higher.  Use a nylon through hull fitting with stainless steel hose clamps at the transom. 
   - DO NOT connect the pump discharge hose to the SJ23 cockpit drain tubes.  In nasty weather you will need all the flow these tubes can provide to drain the cockpit.  Besides, once the boat is low in the water the pump water may flow into the cockpit, instead of overboard.
6. Support all discharge hoses to hold their weight when full of water and to prevent movement as the hull yaws with the motion of the waves.  An unsecured hose will eventually fatigue and break off, creating a hole to sink the boat.  Exactly the sort of thing you're trying to avoid!  
   - I've chosen to install wood cable trays on Panache to support the discharge tubes.  Or you could glue wood blocks (epoxy saturated) to the inside of each SJ23 locker wall then equip each with a clamp and you have a secure system to support a hose filled with water.
7. If you have to make a decision as to where to install your first automatic bilge pump, make it the bottom of the port locker.  The second choice should be at the lowest part of each settee and your final choice is just aft of the knot meter.  If each is equipped with a float switch you have full automatic operation.
8. FLOAT SWITCH - Since the SJ23 settee lockers have a flat bottom, a lot of water can settle there before a float switch would switch on.  I have found a solution to detect 1/2" deep water and will test it this summer.  A standard nautical design operates when the water is deeper ON-2",  OFF-3/4". 
   NOTE - I've designed a system for Panache to remove the bottom 1/2" of water and may use a "stilling well" to minimize surface disturbance that would result in the pump switching less with water sloshing in the bilge.
9. If your outboard doesn't have a generator, you have no choice but to install a good backup manual pumping system.  A fully charged battery can likely operate the 3 pumps for about 1 hour.  When the water reaches a foot deep the death of a liquid filled battery is imminent.  At this point in time you better have your life jacket on, your ditch bag handy and have sent a mayday on your VHF.  See how quickly your standby electric system becomes ineffective!  I really like Bret's installation of a manual backup pump in case the power dies.
10. If your outboard has a generator then start it immediately to operate the pumps, keep the battery charged and point the boat to shallow water.  Beach it with the center board up.  If each pump is equipped with it's own float switch they start independently as needed.  Since the weight of sloshing water will likely pull the leaking end of the boat down, it leaves the other automatic pump high and dry, AND switched off.  This way you conserve power for the pump that is submersed.
11. I doubt you can install a large enough electric bilge pump to deal with a massive leak.  For this you need a very large capacity emergency pump as carried by a salver.  Lets hope the salver is never required.

WIRE THE BILGE PUMP - See Tech Tip E16 for wiring considerations.
 

BRET'S MANUAL COCKPIT PUMP INSTALLATION.

"I didn't have a pump installed on my boat and needed one to be compliant for PIYA / PHRF legalities for some racing I was doing.  I devised this manual system recognizing the fact that when a person is in a sinking situation they are NOT going to be very clever or creative so they need a pump that is simple to operate and is extremely reliable.  These two points can't be emphasized enough.  In a desperate situation a person can be fast or clever, hardly ever both.  That's it for man kind! 

It probably wouldn't be a big deal to race without a pump from a rules standpoint but if I didn't have it and if something went wrong, the insurance company would probably have something to say about it!  Both of these points are ancillary issues compared to saving a life.  The fact is that no boat should be without a pump and a single handed sailor isn't going to get the water out with a bucket!  Here's what I came up with to overcome the compartment issue."

The output tube and fitting are permanently attached to the transom for overboard discharge.  The transom fitting is installed at seat height as there is no point in placing it higher than the bottom of the tiller notch.  The pump can easily function with water discharged at seat height (I don't even like typing this!).  The back pressure from pumping slightly uphill is not a problem. 

I also bought 20' of pickup tube and installed a strum box to the end.  The tube is permanently attached to the pump and stows coiled up underneath the cockpit ready for use.  BOTH the input and output tubes are the SAME SIZE which is very important to ensure flow volume.  The fact that they are non-collapsing ensures that you can't pinch a hose during this crucial time.  
The end of the pickup tube is long enough to reach any compartment in the boat.  This way if I hole the boat at the bow or below a settee I can shove the tube into that compartment and head back to the cockpit to pump and steer if I need to.  The strum box on the end of the tube minimizes any chances of a plug.  This long hose also lends itself to pumping the dinghy dry or to drop into an adjacent boat to render assistance.

I have tested this installation by pumping water out of a 3 gallon bucket from within the salon and emptied it in about four pump cycles.  I was very satisfied with the performance.  Most importantly it is very simple and doesn't rely on electricity or complex valve systems.  The only part of the installation I would change is the location of the output fitting as it is too close to the outboard engine for my liking.  I didn't realize how much water would come out when you pump really hard.  It can push a stream of water 3' straight out the fitting.  So you can see that it's quite a fire hose!  My current placement will work but it should be away from the engine on the port side.    Bret.
 

SAFETY NOTE 1:  A removable through hull knot meter is always installed inside a through hull fitting, using a couple of O-rings seals to keep out the water.  The O-rings should be lightly lubricated with lithium or silicon grease to stay pliable and to prevent damage as they slide in.  Most knot meters are also equipped with a cap to seal the through hull fitting when the impellor is removed for inspection.  BOTH the impellor and the cap SHOULD be attached to the through hull fitting with 1' of strong line to prevent either from rolling away to the dark reaches of the bilge where you can't reach it.  This simple action really shortens the time to find the fitting, even if the water is so deep that you have to dive in and work by feel. 

SAFETY NOTE 2:  The same goes for any other thru hull fitting that doesn't have a valve (i.e.: cockpit drains).  If the hose comes off or cracks you have an instant leak to contend with.  Jam a close celled foam plug in the hole.  This ready made plug comes in a cone shape to fit most any hole.  I think this is superior to a wood plug since it can seal an odd shaped or rough hole.  Small toy footballs are sold in Dollar stores that fulfill this requirement quite nicely.  They work very well if your SJ23 is equipped with a cross bar in the through hull fitting.  For this reason I keep several "footballs" onboard Panache. 
- Alternatively keep a tapered soft wood plug tied to each through hull fitting to plug it.  Teak works very well.  You may have to drive it in with a hammer or other heavy object to get a reasonable seal.  You can usually get a better seal if the plug is driven in from the outside but you can likely seal it quicker if it is driven from the inside.  I'll let you decide which direction to use.  I don't have alligators to contend with where I live!  Tapered plugs are usually available in sizes to fit a range of holes.  Examples are: 1/8" to 1 3/8" or 3/4" to 1 7/8".  They are required for most race categories as standard safety equipment.  Either of these definitely make sense on a cruising boat. 
 

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