Bilge Pump Location

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eodjedi
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Bilge Pump Location

Post by eodjedi »

Ok so I'm ready to finally put a bilge pump in. Location is obviously a key factor and trying to determine whether or not I will use one, or two pumps. If using one pump, I was thinking of installing a single pump center just behind the battery location underneath the rear bedding. This will mostly be for emergency purposes as I do not see a lot of water pooling up in that spot, but it is the lowest point from what I can tell.

Second option would be two port and starboard. One under the starboard dinette seat and the other under the sink port side. I have my A/C plumbing located there.

So question is, do I really need two? Can I get away with one?. Please respond with ideas and pictures of your setups. This is pretty much the last mod of the year, unless I get around to installing a Natures head.
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Jimmyt
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Re: Bilge Pump Location

Post by Jimmyt »

That’s where I put mine. My thinking was, the plastic through-hull and engine well drain are the most likely failure point - that I won’t have caused. If I hit something, then the pump may or may not be at the lowest point due to water intrusion. At any rate, I’m hoping to get back to the ramp with bilge pump assist rather than waiting on the deck of my unsinkable boat... for someone else to save me.

You need as many as it takes for you to enjoy using your boat. One was enough for me. If you and crew can always swim in warm water to land, zero would work. An unsinkable boat is a wonderful thing.
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Herschel
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Re: Bilge Pump Location

Post by Herschel »

Jimmyt wrote:That’s where I put mine. My thinking was, the plastic through-hull and engine well drain are the most likely failure point - that I won’t have caused. If I hit something, then the pump may or may not be at the lowest point due to water intrusion. At any rate, I’m hoping to get back to the ramp with bilge pump assist rather than waiting on the deck of my unsinkable boat... for someone else to save me.

You need as many as it takes for you to enjoy using your boat. One was enough for me. If you and crew can always swim in warm water to land, zero would work. An unsinkable boat is a wonderful thing.
I opted for a "portable" bilge pump. I have it in a plastic container with several feet of flexible tubing and electrical hookup ready to plug into a "cigarte lighter" type 12-volt plug so I can deploy it where needed. While I do keep my boat in a slip at a marina, I figured there was little chance that our boats would "spring a leak" just sitting there. Rather, I am more apt to find water build up from a topside leak, a patially open hatch, or a fresh water tank malfunction. And just need to do some bailing. I like the idea of being able to put the little pump where I need it.
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sailboatmike
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Re: Bilge Pump Location

Post by sailboatmike »

If you have one you may have to wait until any water ingress makes its way around the ballast tank before it can draw any water, personally I have one at the moment under the furthest forward rear buck hatch, the pump is attached to the galley sink through hull, this really isn't optimal so I think I wall go for 2 smaller ones, one each side and attache the starboard outlet to the head sink outlet.
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Starscream
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Re: Bilge Pump Location

Post by Starscream »

I put mine under the galley, epoxied to the lowest part of the floor that I could reach. I know that the X has several individual bilges that are almost separate compartments, but I figure that if I really NEED! a bilge pump, the water will quickly be high enough that it will find its way in there so that the pump can buy me a few more seconds of panic.

I drilled a hole through the side of the boat above the hard-chine and installed the drain hose with an anti-backflow device. I also rolled up a small piece of bugscreen into a little cone and placed it just inside the through-hull fitting, loose enough that the bilge pump would just blast it out if it ever activated, but enough to stop the ever-present river spiders from finding a new hole to block up.

I used a white plastic through hull fitting from PERKO, not a cheap chinese knock-off. Didn't want a brass or stainless fitting standing out on the white hull.

The best insurance against NEEDING a bilge pump for an X-boat in my opinion:
http://www.entrepotmarinemart.com/en/dr ... ses32352-2

Fits in the motor-well drain exit hole. Even though I know of no documented failures of that drain system, it gives me the heebie-jeebies every time I see the water coming up into the motor well when we are out on the water. That happens a lot when we are anchored and swimming off the back of the boat: the motor and several people lined up taking turns climbing down the swim ladder submerge the stern enough to push water up into the well.
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Russ
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Re: Bilge Pump Location

Post by Russ »

Herschel wrote:I opted for a "portable" bilge pump. I have it in a plastic container with several feet of flexible tubing and electrical hookup ready to plug into a "cigarette lighter" type 12-volt plug so I can deploy it where needed. While I do keep my boat in a slip at a marina, I figured there was little chance that our boats would "spring a leak" just sitting there. Rather, I am more apt to find water build up from a topside leak, a partially open hatch, or a freshwater tank malfunction. And just need to do some bailing. I like the idea of being able to put the little pump where I need it.
This makes the most sense to me.

From the factory, our boats have no thru hulls, shaft log or rudder posts to leak. If your boat has thru hull fittings, that's a different story. So any water in the bilge is most likely nuisance rainwater from leaking deck fittings.
A "portable" pump can be placed where needed and has many uses. Having one onboard would make sense to me.

If you "spring a leak" on your boat, it's likely because you hit something. No bilge pump will help you if that happens. Invest in a good floating handheld VHF. Maybe a bucket.

I've never owned a boat WithOUT a bilge pump before. It seems unnerving NOT to have one. After 9 years with the Mac, I'm now okay with not having one.

--Russ
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eodjedi
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Re: Bilge Pump Location

Post by eodjedi »

Well I'm a special case, I do have a through hull. My A/C raw water intake is located on the port side space to the left of the battery housing, the storage area underneath the sink. This is where my main concern is. I can always put a bilge pump there, but I would prefer to have one central pump. I would love to see some examples of other MAC owner installs.
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Jimmyt
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Re: Bilge Pump Location

Post by Jimmyt »

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Image

Image

As stated above, pump is mounted in bilge right aft of battery location. Looped discharge line above discharge thru Hull - which is well above water line. Used stainless thru Hull.

Epoxy’d pump to Hull. These are progress pics, pump is straight now that it’s mounted. I did fuse it, but it’s hooked straight to my house battery. It’s a Rule pump with the magic sensor switch. Still coming to grip with that - may install a manual override.

As you know, protect your wiring. Everything down there is sharp.
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eodjedi
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Re: Bilge Pump Location

Post by eodjedi »

So out of curiosity, what is the purpose of looping the discharge? Should I loop the discharge for my A/C discharge?
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Starscream
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Re: Bilge Pump Location

Post by Starscream »

eodjedi wrote:So out of curiosity, what is the purpose of looping the discharge? Should I loop the discharge for my A/C discharge?
Good answer here:
http://myboatsgear.com/2016/12/26/vented-loops/

For my bilge pump I put the discharge fitting up so high that if it was able to back-siphon seawater it would be the last of my worries. I intentionally didn't loop or vent the line, but I did install it so that the first 8" or so of pipe from the thru-hull into the boat is perpendicular to the hull. So not only would I have to heel over so far that the hard-chine of my X was under water, it would have to be 8" under for water to start coming in the wrong way. Plus, my bilge-pump discharge line has an anti-backflow fitting.
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Starscream
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Re: Bilge Pump Location

Post by Starscream »

On reflection, concerning my last post, I have been over far enough to put the hard-chine under water now that I come to think of it. I've seen waves touch the cabin windows and my wife says she has been able to momentarily see under the surface through them. So I have certainly submerged my through-hull but I haven't seen any water ingress through the bilge pump. Not sure if it's because of the backflow fitting or the way I installed the through hull and piping.
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Jimmyt
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Re: Bilge Pump Location

Post by Jimmyt »

By looping my discharge up near the gunwale, I have to be mostly swamped before water can enter the bilge through the discharge. Minimizes the negative effect of putting a hole in the boat,without using a check valve.

The downside is, the extra piping and turns will reduce my flow rate some. Also, I can’t put more loop in than the pump can overcome initially.

All of this to say, anything you do with pumps and piping should be carefully thought out and/or tested to make sure it will function properly as installed.

Your heat exchanger piping is a different animal. If you get a flooding condition at the discharge, it can relieve through the intake without flooding the bilge (assuming your piping and heat exchanger are intact).

With a bilge pump, if you don’t install a check valve, or loop, you may create a worse situation under certain conditions, where water could enter the bilge through the discharge line. When the pump is not running, water will flow freely through it in EITHER direction.

Sorry if I’m telling you stuff you already know.
Last edited by Jimmyt on Wed Apr 25, 2018 5:10 am, edited 1 time in total.
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eodjedi
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Re: Bilge Pump Location

Post by eodjedi »

Thanks for the info guys. Ill install my bilge pump this week and post photos. I'll probably glass a piece of oak to the fiberglass and mount the pump there. That way I should not have any issues replacing it in case of failure.
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Jimmyt
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Re: Bilge Pump Location

Post by Jimmyt »

Note that the vented loop that starscream linked to is necessary if your discharge will be BELOW the water level. I installed my discharge point in the transom to avoid the heeling submerge issue. I also put it high enough to be out of the water at all times except possibly in a really big following sea condition (where the loop should minimize intrusion due to occasional submergence).

The use of check valves or similar devices as starscream did, are another way to protect from back flow through the discharge. I didn’t want to use a check for my application, but it’s a fine way to go.
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Re: Bilge Pump Location

Post by Tomfoolery »

Jimmyt wrote:The use of check valves or similar devices as starscream did, are another way to protect from back flow through the discharge. I didn’t want to use a check for my application, but it’s a fine way to go.
The use of a check valve is perfectly fine, but with the caution that if the pump runs until it sucks air, it may not be able to restart. The air bubble before the check valve can often give the pump a hard time, as the impeller is sitting in a big air bubble. The pump doesn't even have to pump itself dry - healing can cause the water in the pump and discharge line below the check to drain out and when no longer heeled, the impeller is again sitting in an air pocket it may not be able to pump itself out of.

The solution is to drill a small vent hole just below the check valve so that as the bilge fills with water and floods the pump, or the boat rights itself and refloods the pump, the air can escape and allow the impeller and housing to again be fully flooded.

I know this from personal experience with a keel boat with a deep but narrow and short (longitudinally) bilge that would pump itself dry and not catch a prime on restart. When I removed the check valve, the hose would hold enough to cause short-cycling when it drained back. Setting the switch higher would leave a lot of water in the bilge, but often the pump would still get air bound after heeling steeply. A small vent hole, low enough to not spray around the bilge objectionably with the pump running, solved that problem - reliable restart, every time, and only minimal loss of flow due to short-circuiting back to the bilge.

I might add that when I mentioned it on another sailing forum years ago, it brought howls of protest - "Never put a check valve in a bilge discharge." "Why not?" "It just isn't done." "Why not?" "Never put a check valve in a bilge discharge." :P
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