Bilge Pump Not sealed To Hull

Sea Skipper · Posted: Thu Mar 22, 2007 12:23 am Post subject: Bilge Pump Not sealed To Hull

For some unknown reason this morning I woke up wondering if the screws which were used to secure the bilge pump, battery trays, etc. to the hull bottom had been properly sealed. These screws penetrate into the balsa core and if not sealed could lead to a soft & rotted core as it is normal for a small amount of water to remain in the aft portion of the hull under & just in front of the splash well. Polyurethane caulk squeeze out was observed near the E Q Marine installed battery tray screws, but not under the bilge pump base. I removed the bilge pump (lowest point in the hull) - the factory had not caulked any of the four mounting screws! ' Disgust

' Normally one worries about water penetration into the hull core from the outside, but it can also happen from the inside leading to future costly repairs.

Sea Wolf · Posted: Thu Mar 22, 2007 12:37 am Post subject:

Hank-

Good thinking!

I found the same thing on the bilge pump and gas tank mounts when I first adquired my boat 8 years ago, when it was already 11 years old!

Fortunately, the balsa core is actually little ~1" squares or cubes that are surrounded by resin between them, so the water doesn't communicate from one to the next easily like it would in plywood or wooden stringers.

Best to dig out the bad wood, fill with epoxy, then re-drill the holes and bed the screws in sealant (3M 4200 or something similar) so you can remove them later.

Joe.

Alasgun · Guest

Keep looking, this is kind of like an Easter egg hunt. The more you look the more you will find. None of the screws are sealed anywhere on the boat. I've had to redo my 3 cockpit access ports due to a combination of poor sealing of the hatch to floor and nothing on the screws, resulting in some mighty black, spongy balsa back in a half inch or so!
Mike on Huda Thunkit

ffheap · Posted: Thu Mar 22, 2007 6:08 pm Post subject:

Hi Folks,

When I purchased my 1982 C-Dory, I found the same situation. I went and refastened all the screws, cleats etc. I could get to and resealed them. I found that the inside of the cabin cabinets were all fastened with rusting screws, and I am replacing them as well as the L braces which were not brass, but also rusting. Little by little, it's getting where I want it. I found that there was no water getting in the core on the bottom deck.

For some reason, manufacturers are short changing the boat owners, in that any problems show up long after the warranty is up.

Fred

C-WEED · Posted: Thu Mar 22, 2007 9:10 pm Post subject:

My bilge pumps are stuck right to the sump decks with 3M-4200. No screws to loosen, rust or leak. A good idea considering the wells usually have water in them with swimming dogs on board. It'll be a minor hassle to replace the pumps when they fail. But until then, no worries...

james · Posted: Mon Mar 26, 2007 11:44 am Post subject:

ffheap · Posted: Wed Mar 28, 2007 9:03 am Post subject:

Hi Folks,

In order to get my bilge pump in the small indentation where the plug is located in the stern, I attached it to a board. The pump is attached to a plastic pump holder screwed in to the board. When I want to put the plug in from inside, I hold the board up with a canoe paddle, insert the plug and screw it tight, and drop the board. The board is long enough to go from one side of the bottom of the motor well to the other side. Works great.

Fred

james · Posted: Wed Mar 28, 2007 11:47 am Post subject:

I thought about gluing a board down then screwing the bilge pump to the board.
The problem with that was the thickness of the board would make the pump come on at a higher water level. And would not get the residual water as well.

James

Sea Wolf · Posted: Wed Mar 28, 2007 1:10 pm Post subject:

I have a larger Sea Ray with two bilge pumps, in very inaccessible locations down under two V-6 motors.

We just yesterday had to replace one of the float switches, etc.

Long story short- If the problems were not fairly easy to remedy, I was considering attaching a new pump and switch to a weighted HDPE plastic (cutting board) sheet and substituting the package for the problem equipment, with the advantage being that the entire package could be slid back and forth to it's desired location at the lowest point in the bilge, and then pulled back out as a package for maintainence and service work/repair.

The board could be routed out, groved, and covered with aluminum or plastic screen to lower the pump pick up and limit debris blockage.

For real rough water usage, the package would neeed some rigid support with metal arms fixed to an accessible point.

If I were to build / design a boat myself, this would be a natural inclusion.

Just something to think about!

Joe.