Bilge reconstruction on a 27

[bmiller]

For those not familiar a brief description of how the bilge is formed is in order. The ballast in a CP27 is concrete. The bilge is formed with a plywood form that is left in place after the concrete is poured. The form and ballast are then glassed over making the bilge. Also, the icebox and shower drain into the bilge. Since we do many multiday trips and go through lots of ice this is an issue for Pooka.

My boat gets laid up every winter, during this time projects and maintenance are completed. This winters projects included repainting the bilge. After cleaning and drying out the bilge I noticed a tiny trickle of water seeping back in along a hairline crack in the forward corned of the bilge, thats not good. I opened up the crack a little and more water seeped in, lots more. I thought several holes drilled into the plywood would allow it to dry. More drilling found more and more water. Decided to rip out and rebuild the bilge.

Here are a few pictures.

This first one shows the attempt at drying out via several weep holes.



Here is the plywood form under the glass, note the water and rotted plywood.



The bilge with the form removed, what you see is the wet concrete ballast.



The whole thing was left to dry for several weeks, easy enough here in the dry Rocky Mountains.



The void created by removing the plywood needed to be filled back in. I used cooncrete with very small aggregate to reshape and slope the bilge. After that dried for a few days the whole area was reglassed over with West System epoxy resin fibreglass and two coats of bilgekote.

The finished project.



If you have a boat with a similar bilge I recommend you take a close look at the bilge.

[kchunk]

Bmiller, thanks for the info. I've been thinking seriously about a CP-27 for sale here locally. Question for you, forward of the bilge access is a larger wood panel screwed down. What's under there? I didn't want to take up the floor just to look. My Catalina had a more narrow access in about the same location. This was the bilge on that boat and strangely enough, the compression post (wood) went through the bilge. A rotting compression post is a rotten thing!

[bmiller]

Not much under that next floor panel. The channel that allows water to pass from the front of the boat aft and the glassed oveer top of the ballast. It may take a couple days but I'll get a photo of it posted here.

[Craig Weis]

Your 27 bilge is different then mine. I have no ply wood down there. but rather cement which I depainted so as not to suck up any paint chips in my aux bilge pump. Yours looks great. I use mine for ice and beer. If it rots let it rot. Actually it's just fiberglass and cement. Why seal it? skip.

[MomentSurf]

B, skip, anyone,

Do you guys have any other bildge pumps on your 27s other than the original hand pump?  If so, where are they located and how are they ran...?

[kchunk]

My 23 has two, one hand pump and one electric with 3-position switch, Auto-OFF-ON. The auto position is wired through a float switch. Both pumps are located down in the bilge, where one would expect such a pump  . They are plumbed to the same discharge through the transom via a y-valve and a couple check valves.

Oh, and the bilge pump is the only thing wired directly to the battery or a hot battery bus. This way the battery switch does not have to be on in order for it to work.

Lastly, since your bypassing the switch/fuse panel, don't forget an in-line fuse.

Quick quiz:

1. Is a circuit breaker supposed to protect the wiring or the component in the circuit?

2. Based on your answer to #1, should the breaker be closer to the power source or the component?

--Greg

[MomentSurf]

Thanks for the info k.  I was wondering more of the actual placement on a 27.  I might purchase one very soon and its still on land.  I was wondering where the best spot in the bilge would be to mount an electric pump...the "lowest spot" where the water would run to when the boat is floating.

Hmmm....I'll take a stab at the quiz (I'll base my answers on what I know about transmission systems, I operate bulk power systems for a living (up to 500,000volts - 500kv)).

1- I would say both.  The circuit breaker should protect everything on the circuit.  The fault current will travel from the source to whatever is creating the fault, potentially destroying any equipment or wire it passes through on its way.
2-The breaker should be mounted close to the power source, where the fault current is coming from.

[brackish]

My understanding is the wiring.  Often multiple components are on a circuit with different current draws.  many times they have their own protection, fuses or thermal overloads.  In fact, most marine devices other than lighting usually have their own in-line fuse and they protect the device as they normally will trip or blow at a much lower amperage than the breaker they are tied through.  The circuit breaker is designed to trip in the event of an overcurrent or fault that exceeds the capacity of the total circuit design.  While it may protect the device, it cannot be depended on to protect it.

As far as distance, the breakers are tied to a hot buss with an ampacity to carry the number of breakers that will be on that buss in the panel.  Essentially, they are always at the source.  There may or may not be a main or protection from the battery to the buss.

[bmiller]

If it rots let it rot. Actually it's just fiberglass and cement. Why seal it? skip.

If left unsealed water will migrate down between the concrete ballast and sides of the hull. If the boat sits out of the water during winter months freeze thaw can wreak havoc. Not to mention the thought of stagnat water sitting in the bottom of the boat.

As for where to place the electric pump and switch there's really only one place. The bilge is pretty small and well sloped. I'll get a photo pretty soon of how mine looks.

[Craig Weis]

Ah yes. Didn't think about freezing and my boat sits inside but not heated and very dry.
I figured the bilge water, a tiny little amount, would evaporate first.
Since boat hulls can be made of cement turning to concrete over the years, Portland Cement Corporation suggests that non-expanding cement [that would be cement with limited shrinkage] used on bridges, roads and structures may require as much as 88 years to fully cure, that this material is pretty water tight.
If I had 'that' much water in the bilge I'd have much larger problems and likely would just scrap the hull if the leak could not be found. Or just grind off a hole in the foot of the keel and wait till it stopped dripping, then do the patch-up.

[DH]

OK guys where are the pictures. I got all the problems. Little ones, but many ones.

[Allure2sail]

Hi Guys:
Does your boat have a flange and drain plug on side of the keel? If you don't drain this every winter it will freeze and crack the floor in the bilge box when it expands. The surveyor I hired never even looked in the bilge, that is why I will never use or recommend him again. No matter how well your keel is sealed you will always get water in the keel shell that houses the cement and lead ballast. If that isn't drained come wintertime you end up with a cracked floor in the bilge box. My boat had the drain plug but the previous owner never drained it and it sat like that for two winters. I now take it out for the winter and leave it out until the springtime bottom sanding and painting. I had to gouge it (bilge box) all out and re fiberglass it back together. I also just replaced my second West Marine 1000 gallon cartridge style bilge pump in two years with a RULE 1500 pump (hopefully this brand will last more than one season). Along with the pump I upgraded to a larger discharge hose and through hull out the stern. This bilge box cracking and repair I believe has been discussed by a few of use before, try a search for more info.
Good luck...
Bruce