Want to ensure bilge pump backup. Only have one thru hull. Can I "Y" the output hose with one way valves at each pump?
Dual bilge pumps
- Thread starter mjmercer19248
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yes but ... One-way valves eventually get clogged because of their inherent design feature, the valve. It is not a good idea to use those in a bilge pump hose. Using an inverted loop arrangement will serve the same purpose with no danger of getting stuck.
Having one-way or check valves in the bilge is one risk not worth taking. They do clog and fail but the worst is that they may go unoticed until water starts coming up the floorboards. I have always referred to automatic bilge pumps as convenience rather than safety items. They do a good job of discharging overboard incidental water that accumulates in the bilge without us having to do work but as far as safety they have no real capacity to deal with any significant inflow of water. Based on this I have redefined my thoughts about the practicality of installing a backup pump. With little safety to be gained I guess I can deal with the temporary interruption of convenience should the pump fail. Besides having two pumps just doubles the possibilities where something could go wrong. I'm not advocating to eliminate backup pumps for those that have them but to provide some food for thought for those that may be considering an installation and urge them to think things through. There is no substitute for checking up on the boat frequently but for those that cannot, if a 2nd pump brings some peace of mind, go for it. Keep up regular inspections and maintenance as they provide the safety.
Don't know about the 37, but for the 1980 36, the bilge pump thru-hulls are up high on the tops sides, only a few inches below the toe rail. Cutting/installing a new marlon, or nylon thru-hull is pretty quick. That was my solution for an extra bilge pump.
Another thought: Are you planning to ever use your shower? If not, than the shower sump pump hose/thru-hull is easy to convert to bilge hose duty.
Another thought: Are you planning to ever use your shower? If not, than the shower sump pump hose/thru-hull is easy to convert to bilge hose duty.
Separate exhausts for the bilge pumps. I did this last year - peace of mind. The float switch for the secondary pump is higher.
Bilge pump outlets
I would always assign a separate through-hull for each overboard discharge and would never buddy them up on each other. That sort of confuses and contradicts the whole point.
For what it's worth, here are some thing about bilge pumps I have learned in 40 years of this business:
The bilge pump's discharge should/must be absolutely as HIGH as possible on the hull. Imagine the circumstances if the boat were taking on water so that the discharge outlet found itself underwater. Then imagine that one of the bilge pumps' discharge outlet is the reason the boat is taking on water. You want to eliminate any possibility of a water-laden boat taking on MORE water.
The overboard-discharge outlets for important pumps should never be white nylon.
At Cherubini some early 44s had bilge pumps discharging into the cockpit, because we had very big cockpit scuppers hard-plumbed out the hull. This was a risky idea because if the cockpit drains are what's causing the leak, you are contributing to the problem by running the pump. Believe or not the reasoning behind this was that owners didn't want to mar the beautiful topsides with bilge-discharge stains. This is foolish wisdom and vanity into the bargain. I recommend(ed) to all owners of C44s to have this remedied ASAP. But the point can be taken by anyone with any boat. The clearer the way out, the better.
At Cherubini we devised the 'bilge-pump-on-a-stick' system. The sump in that boat is very deep-- about fingertips'-depth for a moderately tall man lying on the galley sole. We mount the electric pump at the bottom of a Starboard plank that gets bolted, with a wingnut, only at the top. To service it, you remove the wingnut and lay the whole thing on the cabin floor. It is fitted with only just enough cheap swimming-pool hose to give you this much room-- the rest of the run was properly done in seawater hose with wire reinforcement.
Later we added a second pump above the first, fitted with an indicator light mounted on the panel (and sometimes an alarm). If the water rises past the first pump and activates the second, you find out about it, so you know you have a bad primary one and only 8 more inches in this narrow, deep sump. You could mount them closer together if you wanted earlier warning; but we mount them one atop the other because the well is only so narrow.
A grey-water tank's evacuation pump can be a bilge pump. Provide a 1-1/2" or 2" plug in the tank that would effectively drain it into the bilge. When you remove the plug, the bilge water flows into the tank, the tank is then part of the bilge and that pump will assist you.
With a Y-valve, a holding-tank pump will do the same thing. Consider the capacity of most macerator pumps.
With a Y-valve, a seawater-washdown pump will do the same thing.
With a Y-valve, the engine cooling-water pump will do the same thing. This pump has amazing capacity-- more than once such a system has saved the whole boat mostly by itself.
On the last C44 we gave it 7 ways of getting water out of the bilge; and this boat has internal ballast and what has to be the strongest hand-laid hull in history. Except for a faulty hose I really don't know how a C44 bilge would ever take on seawater.
A manual pump should be mounted where the helmsman can work it. Sending a crew member below or to somewhere else to work the manual pump leads to communication gaps and is only a good system if you have the able-bodied crew member under such circumstances to spare for this task.
In my experience the best manual/primary bilge pump in the world is the Royal-Navy-spec Whale Gusher 30 with two diaphragms (will work with one ripped, at half capacity). It costs about $300 and is worth every cent.
I have the miniature version of this on my H25, the Gusher 10. It's about $100 and is worth every cent.
The further-curious might seek Seaworthy, by Bob Adriance who was the BoatUS adjuster for many years.
I would always assign a separate through-hull for each overboard discharge and would never buddy them up on each other. That sort of confuses and contradicts the whole point.
For what it's worth, here are some thing about bilge pumps I have learned in 40 years of this business:
The bilge pump's discharge should/must be absolutely as HIGH as possible on the hull. Imagine the circumstances if the boat were taking on water so that the discharge outlet found itself underwater. Then imagine that one of the bilge pumps' discharge outlet is the reason the boat is taking on water. You want to eliminate any possibility of a water-laden boat taking on MORE water.
The overboard-discharge outlets for important pumps should never be white nylon.
At Cherubini some early 44s had bilge pumps discharging into the cockpit, because we had very big cockpit scuppers hard-plumbed out the hull. This was a risky idea because if the cockpit drains are what's causing the leak, you are contributing to the problem by running the pump. Believe or not the reasoning behind this was that owners didn't want to mar the beautiful topsides with bilge-discharge stains. This is foolish wisdom and vanity into the bargain. I recommend(ed) to all owners of C44s to have this remedied ASAP. But the point can be taken by anyone with any boat. The clearer the way out, the better.
At Cherubini we devised the 'bilge-pump-on-a-stick' system. The sump in that boat is very deep-- about fingertips'-depth for a moderately tall man lying on the galley sole. We mount the electric pump at the bottom of a Starboard plank that gets bolted, with a wingnut, only at the top. To service it, you remove the wingnut and lay the whole thing on the cabin floor. It is fitted with only just enough cheap swimming-pool hose to give you this much room-- the rest of the run was properly done in seawater hose with wire reinforcement.
Later we added a second pump above the first, fitted with an indicator light mounted on the panel (and sometimes an alarm). If the water rises past the first pump and activates the second, you find out about it, so you know you have a bad primary one and only 8 more inches in this narrow, deep sump. You could mount them closer together if you wanted earlier warning; but we mount them one atop the other because the well is only so narrow.
A grey-water tank's evacuation pump can be a bilge pump. Provide a 1-1/2" or 2" plug in the tank that would effectively drain it into the bilge. When you remove the plug, the bilge water flows into the tank, the tank is then part of the bilge and that pump will assist you.
With a Y-valve, a holding-tank pump will do the same thing. Consider the capacity of most macerator pumps.
With a Y-valve, a seawater-washdown pump will do the same thing.
With a Y-valve, the engine cooling-water pump will do the same thing. This pump has amazing capacity-- more than once such a system has saved the whole boat mostly by itself.
On the last C44 we gave it 7 ways of getting water out of the bilge; and this boat has internal ballast and what has to be the strongest hand-laid hull in history. Except for a faulty hose I really don't know how a C44 bilge would ever take on seawater.
A manual pump should be mounted where the helmsman can work it. Sending a crew member below or to somewhere else to work the manual pump leads to communication gaps and is only a good system if you have the able-bodied crew member under such circumstances to spare for this task.
In my experience the best manual/primary bilge pump in the world is the Royal-Navy-spec Whale Gusher 30 with two diaphragms (will work with one ripped, at half capacity). It costs about $300 and is worth every cent.
I have the miniature version of this on my H25, the Gusher 10. It's about $100 and is worth every cent.
The further-curious might seek Seaworthy, by Bob Adriance who was the BoatUS adjuster for many years.
Dual bilge pumps should be completely separate systems. Each should have its own discharge thru hull near the toe rail as the others said. Also, they should be wired to separate batteries and fuse protected.
Additionally, my primary pump, which is lower in the bilge, is on a digital bilge pump counter so it can't mask a problem. The secondary, or backup, is higher in the bilge and it is on an alarm.
When I bought the boat, it had only one bilge pump, and the discharge thru hull, while up near the toe rail and as close to the pump as possible, was located...get this...behind the electrical panel! I don't know if that arrangement was original or not, but since water and electricity are generally not a good combination, I moved the discharge to the opposite side of the cabin inside a galley cabinet and put a dummy thru hull fitting (from MarineEast.com) in the old location rather than glassing it in.
Additionally, my primary pump, which is lower in the bilge, is on a digital bilge pump counter so it can't mask a problem. The secondary, or backup, is higher in the bilge and it is on an alarm.
When I bought the boat, it had only one bilge pump, and the discharge thru hull, while up near the toe rail and as close to the pump as possible, was located...get this...behind the electrical panel! I don't know if that arrangement was original or not, but since water and electricity are generally not a good combination, I moved the discharge to the opposite side of the cabin inside a galley cabinet and put a dummy thru hull fitting (from MarineEast.com) in the old location rather than glassing it in.
Recently added a second bilge pump on my Cherubini 44. It is a super sub 650 model and really just keeps the bilge dry (less than 1 in. of water). I wasn't keen on putting another hole in the hull so I just tapped into the emergency manual discharge pump line with a Y valve. Of course it has its own anti syphon loop and seems to work great. The manual bilge pump is unaffected by this arrangement so I think this is a case where doubling up is OK. It probably would not work if this second bilge pump were a larger capacity pump as I would not be able to use both pumps simultaneously.
Quadruple bilge pumps?
I may be crazy, but I plan to have 4 bilge pumps in Fred V when her refit is finished:
1. Electric - Whale Gusher 30 for major pump out
2. Electric - smaller auto type to keep bilge as dry as possible
3. Manual - in cockpit
4. Manual - in main cabin
And all will have their own thru-hulls located as high as possible.
I may be crazy, but I plan to have 4 bilge pumps in Fred V when her refit is finished:
1. Electric - Whale Gusher 30 for major pump out
2. Electric - smaller auto type to keep bilge as dry as possible
3. Manual - in cockpit
4. Manual - in main cabin
And all will have their own thru-hulls located as high as possible.
FredV is spot-on
I like FredV's plan for reliable pumps and redundancy. Mind though that the Whale electric pumps are expensive and there is plenty out there much cheaper. My preference for Whale extends to their manual pumps, which are the very best. A decent Johnson electric bilge pump and solid-state Water Witch-type switch should suffice for most of what we use out boats for. At about $45, the Johnson can be backed up with another pump carried 'in stock' on board in case the one in situ packs it in. If that should occur in an emergency, the Whale 20 or 30 manual Gusher pumps will do a fine job till the change-out can be effected.
I like FredV's plan for reliable pumps and redundancy. Mind though that the Whale electric pumps are expensive and there is plenty out there much cheaper. My preference for Whale extends to their manual pumps, which are the very best. A decent Johnson electric bilge pump and solid-state Water Witch-type switch should suffice for most of what we use out boats for. At about $45, the Johnson can be backed up with another pump carried 'in stock' on board in case the one in situ packs it in. If that should occur in an emergency, the Whale 20 or 30 manual Gusher pumps will do a fine job till the change-out can be effected.
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