The Malo 39 is a dry boat. That is – water does not seem to run into it all of the time like my old Hunter 34. All of the typical places where water use to leak in don’t exist. The shaft seal is oil based, so does not need water as a lubricant, and there seems to be minimal condensation in the bilge. Also, the toe rail does not leak. So, with this in mind, the bilge pump Malo installs drains the sump at the aft base of the keel. This sump is pretty deep – so if all of the water decided to run out of the engine – it would end up in this sump. This bilge pump also functions as a shower drain – just to give you an idea of its capacity – which is about 2-3 gal per minute. Not really much of a bilge pump.
Malo also installed a wonderful high capacity manual bilge pump with a 1 1/2" hose that ran from the bottom of the bilge to a 1 1/2" stern outlet. This was the perfect arrangement, but was dedicated to the hand pump.
I knew this was a problem when ordering the boat, but again, there did not seem to be much to do about it. So, I decided to install a bilge pump after about six months of ownership. I wanted this automatic, so there was some hope that if something blew out while we was away, the boat would have some chance of not sinking. This idea about the boat not sinking became very important to me – I realized that MS would be very upset if this happened, and I would probably be in a lot of trouble- so I devoted about three months to the comedy of errors that was this upgrade.
Malo constructs a little ledge in the keel that seemed about right for the Rule 3700 – this was the biggest pump I could get in there. It takes about 17 amps, is rated at 20, and claims to pump about 3700 gal per hour. Practical Sailor tested this pump with about 3 feet of head on it, came up with the amp rating, and found that it pumped about 2000 gal an hour. That’s pretty good, only 1700 gal per hour less than Rule claimed!! It would take care of inflow from a 2-3" hole in the boat – the failure of one thru-hole. The problem was, how to exhaust the water from the pump – its takes a 1 1/2 inch hose.
Here is the Rule with the water sensor. The water has to raise up above the pump, and hit the sensor. It was a little exciting when I was flooding the bilge to see how this would work – I made sure that MS was not due home soon……
A slightly different view of the pump in the bilge. This is about 2 feet down from the sole. I mounted the pump on a piece of wood first that was cut from a template, then glued it down.
The best info I have found about bilge pumps is from Nigel Calder. Several things create problems for bilge pump installation, according to his rules. First, no check valves to inhibit flow. Second, no taping into deck scuppers or dedicated hull outlets – since this could backflow into the pump in all kinds of circumstances, and, would require a check valve. Then there is the head issue, and diminished capacity based on the number of 90 degree turns. When I had reread his stuff about a dozen times, I decided it might be best to get a couple of buckets, and always keep a few scared sailors around….
My first attempt at the installation was stringing 40 feet of 1 1/2" bilge hose from the pump and tying it into the stern bilge exhaust with a tee fitting. All of this white hose ran from the sump through the port and aft lazerette. This sort of worked, but was a silly, stupid installation that took many holes and several weeks of time. When I was done I felt like an idiot, and went back to the drawing board.
I then came up with the bright idea of taping into the existing hose, and exiting the water through the hand pump. This was a diaphragm pump with, naturally, a check valve in it. Anyway, I was at a loss, so decided to try it. Nowhere could I find a reason why this would not work.
Here is the "y" junction tapped into the original Malo bilge exhaust line. You might notice that I ran out of hose clamps for double clamping – need to fix that someday…
I used a garden hose to try and flood the boat, and the pump kept up fine. The existing hose from Malo runs right along the base of the boat and out the stern – there is very little head, which probably helped. I was only flooding with about 500 gal per hour, though.
A major problem was getting the pump to drain the water out completely, and not recycle water as it backflowed into the bilge. This was solved by installing a switch that used a water based sensor to activate the pump, and had an eight second delay – this allowed the pump to completely exit the water from the bilge. I also remembered to test the manual pump – it still worked!
Here is the auto bilge pump switch. There is also an Aqua-alarm bilge monitor down there in the bilge, but that is another story. Wiring is 10 gauge, run directly off of the main bus with an in-line 20 amp fuse.
In hindsight – I would have asked Malo to install a separate drain line for a high capacity pump, which they would have been happy to do and would have been quite easy at the time. I have a small amount of comfort with this pump, (probably amount as much as I have with any electrical appliance on which my life might depend), which seems to work quite well, and maybe would handle a failed thru-hull if we were off of the boat.
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