And I'm not alone! My bilge pump sometimes doesn't start against the head of about four feet of water beyond the check valve; it starts pumping 90% of the time; the rest of the time it just spins. So I decided to remove the check valve but then I have the problem that after pumping, the water in the 15 feet of hose drains back into the bilge. The pump starts again and repeats and repeats and .... I've tried two bilge pumps (Rule 2000) and two check valves. I also looked for a switch that had a larger height difference ( need two inches) between on and off to no avail. Upon discussing the problem with others in my marina I found I was not alone! I see no practical way of shortening the hose in my boat (Hunter 34; in fact if I do away with the check valve I plan on adding a vented loop; that will make my problem worse; more hose and more height. The only place for the vented loop is near the discharge. Any suggestions?
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Eric Lorgus
Bilges are either dry or wet
Al, In a perfect world, we'd all have dry bilges and the pump would be rarely used. I have two Hunters, and both boats have wet bilges, to my chagrin. On the 28.5, the icebox & shower drain to the bilge. I have no check valve, so even when the pump comes on, it can't get the bilge dry, because of the small amount of water in the hose that will slide back down into the bilge when the pump shuts off. The only way to get the bilge bone dry is to use a small hand pump to suck up the residual. On my 54, there's a fresh water leak somewhere that I haven't found yet. I have 2 pumps on the 54, a low pump which is the one that operates normally, and a high pump (Rule 2000) as both a backup to the low and as an auxiliary in case I spring a big leak. I haven't tried using check valves to prevent backflow. It sounds like your experience is that they create too much pressure for the pump to open them. My concern would be if there's any chance of the valve sticking, the pump can't work. Don't know if this helps at all. Sounds like one of those problems with no easy cure. Eric Lorgus
Al, In a perfect world, we'd all have dry bilges and the pump would be rarely used. I have two Hunters, and both boats have wet bilges, to my chagrin. On the 28.5, the icebox & shower drain to the bilge. I have no check valve, so even when the pump comes on, it can't get the bilge dry, because of the small amount of water in the hose that will slide back down into the bilge when the pump shuts off. The only way to get the bilge bone dry is to use a small hand pump to suck up the residual. On my 54, there's a fresh water leak somewhere that I haven't found yet. I have 2 pumps on the 54, a low pump which is the one that operates normally, and a high pump (Rule 2000) as both a backup to the low and as an auxiliary in case I spring a big leak. I haven't tried using check valves to prevent backflow. It sounds like your experience is that they create too much pressure for the pump to open them. My concern would be if there's any chance of the valve sticking, the pump can't work. Don't know if this helps at all. Sounds like one of those problems with no easy cure. Eric Lorgus
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John
Wow
That's interesting. I wonder where the discharge is? I bought a couple of Rule 2000 gph pumps and switches, and just assumed I would install the discharge through-hulls in the transom; but it occurred to me recently that I should consider discharging right out the side of the hull, just below the rub rail. This would significantly reduce the amount of hose, and therefore the amount of water that would wash back. Where is your discharge? jv
That's interesting. I wonder where the discharge is? I bought a couple of Rule 2000 gph pumps and switches, and just assumed I would install the discharge through-hulls in the transom; but it occurred to me recently that I should consider discharging right out the side of the hull, just below the rub rail. This would significantly reduce the amount of hose, and therefore the amount of water that would wash back. Where is your discharge? jv
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Mark Johnson
"I feel your pain"
I had a Catalina 42 with the overboard discharge for the bilge pump just slightly above the water line on the transom. When under power the stern would squat down and the bilge pump discharge would reverse syphon back into the bilge even with a loop in the discharge hose. My solution was to put a check valve in. That indead stopped the reverse syphoning, but it created another problem...if the bilge pump had to cycle on again within a short amount of time it too became blocked with water in the discharge hose and would not pump. It ran OK, but did not pump any water. I never did come up with a adequate solution to both problems. It's not a good feeling to see water in the bilge that you can't pump it out.
I had a Catalina 42 with the overboard discharge for the bilge pump just slightly above the water line on the transom. When under power the stern would squat down and the bilge pump discharge would reverse syphon back into the bilge even with a loop in the discharge hose. My solution was to put a check valve in. That indead stopped the reverse syphoning, but it created another problem...if the bilge pump had to cycle on again within a short amount of time it too became blocked with water in the discharge hose and would not pump. It ran OK, but did not pump any water. I never did come up with a adequate solution to both problems. It's not a good feeling to see water in the bilge that you can't pump it out.
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John J
Bilge pumps
The February issue of SAIL has an article that talkes about this problem. They offer some good advice about different pumps, switches, and discharges.
The February issue of SAIL has an article that talkes about this problem. They offer some good advice about different pumps, switches, and discharges.
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Al Nash
My boat's discharge is located
near the top of the aft, starboard rear quarter. About three feet above the waterline and ten feet aft of the bilge. I want to get rid of the check valve, but the hose drains back so much water that the pump keeps cycling.
near the top of the aft, starboard rear quarter. About three feet above the waterline and ten feet aft of the bilge. I want to get rid of the check valve, but the hose drains back so much water that the pump keeps cycling.
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Ken Palmer
Check vallve works for me
I installed one on my bilge pump for the same reason; water flowing back into the bilge. The check valve fixed my problem. I seem to remember that there is a flapper devise inside the valve, and that it needs to be mounted so that the hinged side is up, letting the flapper close with the help of gravity and the weight of the water behind it. I wonder if that has anything to do with water flowing back into your bilge. Ken Palmer, S/V Liberty
I installed one on my bilge pump for the same reason; water flowing back into the bilge. The check valve fixed my problem. I seem to remember that there is a flapper devise inside the valve, and that it needs to be mounted so that the hinged side is up, letting the flapper close with the help of gravity and the weight of the water behind it. I wonder if that has anything to do with water flowing back into your bilge. Ken Palmer, S/V Liberty
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Peggie Hall/Head Mistress
I would relocate the thru-hull...and--
There's no reason why the bilge pump hose on any boat needs to be 15' long. Figure out where to install a new thru-hull for that's well out of the water, put a loop--not a vented loop, just an arch--in the hose a foot above the waterline. That should only leave you with at most about a quart of water in the line to run back down into the bilge when the bilge pump cuts off. Depending upon how accessible the pump is, you can either reinstall the check valve to prevent it--a quart or so isn't enough to prevent the bilge pump from pushing it just a foot or two...or use a manual pump, bucket and sponge to get that up at end of each weekend.
There's no reason why the bilge pump hose on any boat needs to be 15' long. Figure out where to install a new thru-hull for that's well out of the water, put a loop--not a vented loop, just an arch--in the hose a foot above the waterline. That should only leave you with at most about a quart of water in the line to run back down into the bilge when the bilge pump cuts off. Depending upon how accessible the pump is, you can either reinstall the check valve to prevent it--a quart or so isn't enough to prevent the bilge pump from pushing it just a foot or two...or use a manual pump, bucket and sponge to get that up at end of each weekend.
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Andy Howard
Peggie???
Just curious, Is there any reason why a vented loop should be avoided in a bildge pump line? Also, I've got to install a vent line to my head intake this spring, are the $25 Marelon loops, OK, or should I use the $50 Bronze versions?
Just curious, Is there any reason why a vented loop should be avoided in a bildge pump line? Also, I've got to install a vent line to my head intake this spring, are the $25 Marelon loops, OK, or should I use the $50 Bronze versions?
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Peggie Hall/Head Mistress
Vented loops only required on
hoses connected to below-waterline thru-hulls...bilge pumps exit above the waterline, so there's no way for a siphon to start that could flood a boat--ergo, no need for a vented loop. In the unlikely event a siphon should happen to start inside the boat, count your blessings--'cuz the worse thing it could do is drain all the water OUT of your bilge. And yes, marlon or PVC vented loops are fine, but I wouldn't put one in a vent line.
hoses connected to below-waterline thru-hulls...bilge pumps exit above the waterline, so there's no way for a siphon to start that could flood a boat--ergo, no need for a vented loop. In the unlikely event a siphon should happen to start inside the boat, count your blessings--'cuz the worse thing it could do is drain all the water OUT of your bilge. And yes, marlon or PVC vented loops are fine, but I wouldn't put one in a vent line.
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Walt L.
Why a Big Pump for small water?
How about an idea from an inexperienced neophyte? It seems that everyone is talking about pumping gallons of water with a big pump and backing it up with a really big pump, with quarts to a gallon of water coming back. What if one installed a small pump like a small aquarium pump with a small tube to move the small water out?
How about an idea from an inexperienced neophyte? It seems that everyone is talking about pumping gallons of water with a big pump and backing it up with a really big pump, with quarts to a gallon of water coming back. What if one installed a small pump like a small aquarium pump with a small tube to move the small water out?
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Justin - O'day Owners' Web
la pumpita
Walt - No reason it can't work, but at some point you have a lot of stuff in the bilge. I've also never met a 12v aquarium pump, though there must be something else that would work. Justin - O'day Onwers' Web
Walt - No reason it can't work, but at some point you have a lot of stuff in the bilge. I've also never met a 12v aquarium pump, though there must be something else that would work. Justin - O'day Onwers' Web
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Walt L.
Two Pumps
My thought was one pump to move the big water and one with a small tube. A small pump with a light head could blow the line free of water leaving prehaps less than a cup of water.
My thought was one pump to move the big water and one with a small tube. A small pump with a light head could blow the line free of water leaving prehaps less than a cup of water.
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Leon Sisson
I'm installing 2 bilge pumps ...
I'm installing two bilge pumps. (Well three really.) My 1979 Catalina 25 came with a manual diaphram pump operable from the helm. First I added the smallest, most automatic electric I could find in the lowest part of the bilge I could reach. I adapted its discharge hose diameter from 3/4" down to 1/2" to reduce the volume of drain-back water. This is one of the 500GPH or so Rule pumps that can be set up to start on its built in float switch, but will continue pumping, even after the float turns off, until the pump impellor sucks mostly air. I'm also installing a 3,700GPH damage control pump with 1-1/2" discharge hose. This pump and its float switch are mounted about 2" higher in the bilge than the small pump. Each electric pump will be controlled with the usual On/Off/Auto 3-position switch with pilot light to indicate when that pump is running. I may also wire a loud alarm to the float switch for the big pump. All three bilge pump dischage thru-hulls are located in the transom, as high and close to the centerline as practical. In "This Old Boat", Don Casey discusses this sort of installation in more detail. -- Leon Sisson
I'm installing two bilge pumps. (Well three really.) My 1979 Catalina 25 came with a manual diaphram pump operable from the helm. First I added the smallest, most automatic electric I could find in the lowest part of the bilge I could reach. I adapted its discharge hose diameter from 3/4" down to 1/2" to reduce the volume of drain-back water. This is one of the 500GPH or so Rule pumps that can be set up to start on its built in float switch, but will continue pumping, even after the float turns off, until the pump impellor sucks mostly air. I'm also installing a 3,700GPH damage control pump with 1-1/2" discharge hose. This pump and its float switch are mounted about 2" higher in the bilge than the small pump. Each electric pump will be controlled with the usual On/Off/Auto 3-position switch with pilot light to indicate when that pump is running. I may also wire a loud alarm to the float switch for the big pump. All three bilge pump dischage thru-hulls are located in the transom, as high and close to the centerline as practical. In "This Old Boat", Don Casey discusses this sort of installation in more detail. -- Leon Sisson
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