Dual Bilge Pumps - Yorkshire Rose

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Mark Elkin, Yorkshire Rose #133

Full story and pictures to come.

I've been frustrated by the way the bilge pump and hose system was organized, almost from the moment I bought Y.Rose. The problem is that the hose runs all the way to the stern and rises to the level of the manual bilge pump in the aft cockpit lazarette. When the float switch drops to the 'shut off' point and the pump stops, then all the water still in the hose drains back down and fills the bilge practically to the float switch 'turn on' point.

I will not put a check valve in the hose. Read that advice somewhere. Do not want to add any more resistance to the water flow.

I've tried "smarter" pump switches. Mostly POSs that fail too quickly and are too expensive to replace. So went back to the original Rule float switch.

And have lived with it while dreaming of a better system.

When the last bilge pump failed recently, I replaced it with another that had a higher GPH. While it worked great by itself, to my dismay I found that it actually worked too well! The water in the central bilge compartment would drain very quickly, the float switch drops and turns off the pump, and the water flows back down the hose into the bilge again. And there was not enough time for bilge water in the other (fwd, aft) bilge compartments to drain through the limber holes into the central compartment and be pumped out too.

Some (long) time back, I read an article in one of the boat magazines about that owner's solution to his bilge water problem. His issue was that he had a very deep, steep sided bilge. Due to it's shape, the volume of water was fairly small. And like me, his bilge would empty quickly and refill from water flowing back down the hose. His solution was to put a very low GPH pump down in the bilge and get the smallest diameter hose he could. It would pump slowly, so it ran longer, but more water was pushed up and out the free end of the small hose and did not drain back into the bilge. He also kept a big GPH bilge pump connected that would only turn on if the small one didn't keep up with the rising water level in the bilge. Only problem trying that in our C34s is that we do not have a deep bilge.

But the answer finally came to me. I would also install 2 pumps. Both are at the same level and both are in the main bilge compartment. The float switch for the little one is there too, mounted as the same lowest level. I had the boat yard add a through hull on the side, approx at widest part of the beam of the boat and about 3' above the water line. The little pump empties through this, with only about 6' of small diameter hose. To minimize siphoning if I should be heeled that far -- unlikely, but you never know -- I did install a check valve in this line. Shorter line, less head pressure, so a little resistance was acceptable.

The big pump's float switch is one compartment forward and is elevated about 3/8". If I ever spring a leak that the little pump cannot keep up with, then the big pump kicks in after the water level rises another 3/8. And the pump will keep running even after the central compartment has drained because the switch is in another compartment. When sufficient water from that compartment drains through the limber holes, then the big pump will shut off.

I cannot claim this is a perfect system, but I think it will do a better job of keeping the bilge levels low and the pumps from frequently cycling on-off. It also give the peace of mind that I now have 2 bilge pumps standing ready if the unthinkable should happen.