A25 electric bilge pump discharge location

[nebulatech]

Hi all!

We just had a pop-up tropical storm (it was a tropical depression last night, woke up to find it upgraded to a tropical storm, already moving onshore)! I went to check the bilge on the boat and water in the forward accommodation was above the floorboards. This translates to about 30 gallons. I have a temporary bilge pump and hose that I've been using to fill a 5 gallon bucket, but since I have the galley torn down, I just plumbed the hose to the galley sink sea cock and pumped it directly overboard. Nice.

This little operation had me thinking again of how to plumb my permanent installation. I have the famed whale gusher pump in the starboard lazarette. I'm not sure it works, but I know how to fix it. I was planning to install an electric bilge pump in the keel where the shaft leaves the hull, but I'm uncertain where to plumb the discharge. I could use check valves and plumb to the same outlet as the whale gusher, but I'm not sure this is best, in case the check valves fail. I'm not opposed to a second above-the-waterline thru hull, but I wanted to find out what others are doing.

I'm also considering a second electric bilge pump in the forward bilge area. I'm really not sure where to plumb this to. Initially, I was thinking I could plumb it to a T fitting at the top of the galley sink drain, but that seems like a poor choice. Bilge pumps normally discharge above the water line. I could also run the discharge in the galley cabinetry. Now would be the ideal time to cut the shelving to accommodate since I'm rebuilding it anyway.

I'm very appreciative of your thoughts, considerations and personal experiences!
(I searched the forums, but I was unable to find this specific topic for A25's)

[DesertAlbin736]

This picture shows the bilge pump discharge outlets located under the wheelhouse side window for both of our bilge pumps.

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The forward and aft bilges connect via a copper drain tube that runs under the engine bed, so if you crank up your trailer tongue to tilt the boat up some the water will run back into the keel sump. There is a brass or bronze (?) keel sump drain plug on the port side of the keel a couple feet forward of where the keel starts to curve downward toward prop & rudder that can allow you to drain the bilge IF you can work it loose. I've never tried undoing it on ours, so good luck there. See photo.

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In your case if there's ongoing chances of rainwater flooding you could leave the plug out. Just don't forget to put it back in before launching.

For bilge pumps we have an electric diaphragm pump with the suction hose down in the keel sump. Great pumps but they are quite expensive. Also a backup manual Whale pump attached to the front end of rearmost floorboard cross frame. All inherited from PO. Both discharges routed to just under the side window by the driver seat, so when the electric pump is on I can look out the window & see how much water is coming out & know when to stop pumping. We don't have an automatic float because we don't keep our boat in water full time, but if we did I'd have to add a float switch. An inline suction strainer is required & needs to be checked & cleaned out often. There are times I think I paid too much for our boat, but others when I realize it came with a lot of good things that would have cost a lot to add.

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Example of Jabsco diaphragm bilge pump, $408.57

https://www.hodgesmarine.com/jab36600-0 ... CzEALw_wcB

[nebulatech]

Thanks Steve, all great info as always.

I'm familiar with the keel drain plug but extremely hesitant to mess with it. My yard slopes where the boat is resting so I can't jack it up enough to make the stern the lowest point. I'm a big fan of redundancy for bilge pumps; my sailing mentor had his boat sink at the dock due to a faulty bilge pump. Also, I was reading Nigel Caulder, boat owners handbook last night, the section on thru hulls. There is a very sobering US Navy table referencing gallons per minute inflow based on hole diameter and water depth. Perhaps I'll post it tomorrow. The short story is for a hole much larger than 1.5" diameter, one bilge pump isnt enough.

Therefore I plan to have two independently wired pumps.

[LopezMike]

I have a smallish reciprocating pump sucking from the bilge at the forward end of the rear (behind engine) compartment. This for casual water though it hardly ever runs. Also the apparently standard Whale manual pump under the Stbd. cockpit seat. Each of these has it's own above water through hull on the starboard side. Also, I have a pair of ball valves that allow me to feed the engine raw water input from the bilge. If you open both values at the same time, you sink. Forthwith!

I'm contemplating a very small electric pump with a float switch under the cabin floor just forward of the engine. Under where you stand when doing galley chores. I would block off the under engine pipe at both ends with easily removable plugs. This new forward pump would have, as its primary function, pumping shower water overboard. The thought is to have a grating right under the existing floorboard and an easily setup shower curtain over it and a 2.5 gallon weed sprayer (from my previous boat) which is filled from a tea kettle. This sprayer served me well for a year or two in the tropics. There is a pumper person and a pumpee person and the jobs alternate thus there is an incentive to do a good job pumping.

I will post later about how well this crack brained project turns out. Personally as well as mechanically.

[ssrig]

I have two bilge pumps in the forward bilge, one is a skinny Rule with a float that is approximately 5 inches lower than the other Rule pump that has an internal water sensing voodoo system that I don’t seem to have much faith in but none the less they both drain out from the closet area forward of the head, just below the rub rail.

The other drain is located just aft of the helm in the starboard seat storage area and is midway between the rub rail and the waterline. That drain services a manual whale gusher bilge pump that needs a rebuild. There are several threads with good options for bilge pumps in this difficult location but as for the drain location I just picked a high spot with good access and drilled a hole.

[ssrig]

Oh yeah, I take my bilge plug out for the winter and also give everything a rinse around the PSS and rear bilge area and let it drain through the there before closing the boat up.

I find the two Rule pumps forward look after any water from the rear bilge area by flowing forward through the connecting pipe, the rear bilge water will stay at a certain level never completely draining.

[nebulatech]

...they both drain out from the closet area forward of the head, just below the rub rail.

Thank you, this sounds like a great idea, it's just as high as the galley, but less interference with storage. Also, keeps the drains all on the same side, for observation from the helm as Steve mentioned.

Oh yeah, I take my bilge plug out for the winter and also give everything a rinse around the PSS and rear bilge area and let it drain through the there before closing the boat up.

OK, maybe I'm coming around... I'm afraid the plug will be corrosion-welded in place, but assuming it's not, what do you use, if anything, to seal up the plug? Teflon tape comes to mind...

[nebulatech]

Below is the "flood rate table" From Nigel Calder's Cruising Handbook, published in 2001. A 6" hole 2 feet below the waterline lets in 1000 gallons per minute. Wow!

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I did a quick search of the bilge pumps available at Lewis Marine (wholesaler for the marine industry, I have an account) and found that the highest flow rate available was a Rule 4000 (4000 gallons per hour or 66.7 gallons per minute). Looking at the table, I feel like the 2' depth is the maximum to worry about. I know the keel is below this, but most of the hull apart from the keel is less than 2' deep. Two Rule 4000 bilge pumps would be able to keep up with the flood rate of a 2" hole. Each pump requires a 2" discharge line, so that's something to consider. I also looked at the Whale Gusher Titan hand pump; it is rated at 28 GPM.

One restricting factor with any pump is going to be the size of the intake and discharge orifice. It seems like you need a diameter (combined?) discharge equivalent to the size hole you anticipate protecting yourself against. Then you would also need the power to run those pumps simultaneously. It seems like a loud alarm and a good plan to access and triage the hull breach is in order. Food for thought.

By the way, my (current) "wholesale" cost for a Rule 4000 is $193.85, which is below West Marine, but better prices are found online.

[WillieC]

I was amazed at how easily my drain plug came out. Take your time to remove the 84 layers of bottom paint. I long lamented that I didn’t have a bilge plug, only a slight bump in the bottom paint. When I stripped the bottom to gel coat while prepping for paint a couple years back, lo and behold! Faith and begorrah!

Clean the screwdriver slot to full depth. Get a bigazz screwdriver to fit. Squirt your preferred corrosion buster on it and let it work. You may be pleasantly surprised

And, Stephan at Albinmotor still has replacement plugs. I use pipe dope on the threads and have no issues removing it every year.

[ssrig]

Yup that bilge plug comes out easy as long as the groove is clean and like WillieC says use a big screwdriver and make good contact in the groove....
Mine is brass/bronze plug and was very clean , I don’t use any Teflon or anti sieze and the plug is fine thread so putting back in caution is needed to not cross thread.

Also note my boats on a trailer most of the year hence the plug get a lot of use.

[ssrig]

I have a smallish reciprocating pump sucking from the bilge at the forward end of the rear (behind engine) compartment. This for casual water though it hardly ever runs. Also the apparently standard Whale manual pump under the Stbd. cockpit seat. Each of these has it's own above water through hull on the starboard side. Also, I have a pair of ball valves that allow me to feed the engine raw water input from the bilge. If you open both values at the same time, you sink. Forthwith!

I'm contemplating a very small electric pump with a float switch under the cabin floor just forward of the engine. Under where you stand when doing galley chores. I would block off the under engine pipe at both ends with easily removable plugs. This new forward pump would have, as its primary function, pumping shower water overboard. The thought is to have a grating right under the existing floorboard and an easily setup shower curtain over it and a 2.5 gallon weed sprayer (from my previous boat) which is filled from a tea kettle. This sprayer served me well for a year or two in the tropics. There is a pumper person and a pumpee person and the jobs alternate thus there is an incentive to do a good job pumping.

I will post later about how well this crack brained project turns out. Personally as well as mechanically.

Having a valve set up tp be able to draw raw water from the bilge is a great idea, I have the tools in the glove compartment to quickly remove the intake hose from the thru Hull for that but under pressure with a sinking boat I’m not sure I would get it done, switch a valve sounds better. Any pics of what you did?

Also I find that the under sole area in the front cabin is a good low point on the boat for bilge pumps as the water from the rear bilge flows forward readily and with all the other many drain holes connecting all the bilge cavities, only the rear bilge will hold a few gallons or less down low so maybe plugging the holes isn’t needed. I think the impression I had was that the connecting pipe for the two main bilge areas sloped downward going forward?

[WillieC]

Nope.. Sloped going aft. In water. Not crossing the Strait of Georgia.

[nebulatech]

I'm posting a picture of the side profile of my 1979 A25 thru hull for the galley (1.25") with a side profile of the locking nut for comparison. After much effort, I agree with the online consensus that the easiest way to remove an old thru hull is with an angle grinder. It took longer to fetch it from the garage than it took to remove it.

I,m not sure how useful the picture will be, as I don't know the history of the boat. No way to compare its usage and exposure to galvanic action to yours. I know it spent at least a few seasons on the hard, and was last registered in 1984. But there was extensive water damage on the interior and I bought the boat floating in the water.

You can see severe pitting in the thru hull (right side item) as compared to the retaining ring. Also much thinner, even accounting for the retaining ring being made to be thicker.

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Also, for fun here is the prepped hole. I'm about to make a backing block from woven roving, but I'm still waiting on some colloidal silica to use for bonding it to the hull. I ordered the Groco parts from a dealer in NC (who I found on ebay) for $105. West Marine pricing was approaching 4 time that.

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(This is what your galley looks like, removed.)

[WillieC]

Paint that sucker with bilgekote after you get the thru-hull installed..(Clean, prep and prime first.) It makes a huge feel good difference every time you open the cabinet. And it makes clean up so easy.

[nebulatech]

I've been using Bin 123 oil based stain blocking primer and a high quality acrylic enamel "porch paint" for the interior. This is after I remove the liner adhesive and prep the surface. I have a draft post detailing my method for removing the hull liner.