Location location location - bilge pump and discharge hose

[hectoretc]

On the first day of Christmas, my grandson gave to me, a bilge pump to go in my DSII belly... (sorry... really hard to rhyme that line)



So I have a bilge pump now. My thinking is to install it under the cuddy floor between my battery boxes. Easy access, close to the power and what I presume to be the lowest part of the bilge. Anyone think there is a better place?

It looks to be a 1 1/8" discharge hose, so can I just run it out high on a side maybe up behind the in-seat cooler, or should I route it all the way back to an upper corner of the transom like jdoorly did?

I don't suppose they have a check valve, but if I get the gunwale in the water enough to backflow into the pump, I suspect I'll want to have the pump running at that point anyway in anticipation of the rest of the lake soon to be coming in over the rails.

Very appreciative of anyone with 20/20 hindsights on this as it means cutting a hole in the hull, just as soon do that once.

[jdoorly]

Scott, I don't remember what size tubing (probably 3/4" ID) I used but whatever size fits on the pump output- get that and a through-hull that size as well. I put mine a couple inches forward of the centerboard and a couple inches to port where I made an access port. I screwed the basket to the hull but can remove the upper part of the pump by releasing the plastic prongs. There's a short piece of tubing from the pump to the check valve on the starboard side, then the long tube going uphill to the through hull fitting in the transom so there is about 12-14" of head.

The directions for the pump specified a gradual slope up to the discharge so that's what I did. The check valve theoretically keeps water that was already pumped from coming back to be re-pumped, but I don't think that is working. The check valve valve design doesn't look very robust to me. If you have water getting in the boat due to ingress through the through-hull, I'm sure you will have other water related worries that you should deal with first.

My pump works great although I haven't had much occasion to use it since I rebuilt (with epoxy) my lower gudgeon and bilge drain.

I think the lowest point in the bilge is anywhere between the centerboard and the mast support. I had to re-cut the discharge hole because the first hole was too close to the inside face of the fiberglass coaming (there is extra material there which interfered with the tubing, see below pic). When you install the discharge tube: attach the long tube to the through-hull, run the tube into the hole up to the through-hull, add the caulk or 3m 5200 to the lip of the through-hull then push through-hull home. The other end should be accessible through you battery hole if it didn't hang up on flotation. (I had to cut an access hole just to attach the tube to the through-hull.)

[GreenLake]

From what I read (I haven't used it myself yet) 3M 5200 would be "too permanent" for my taste. Being able to remove this fitting, for whatever reason, would seem prudent. For this application, the superior strength of bond of the 5200 would also not seem to be necessary.

[kokko]

5200 would be a big mistake. You can never get it off

[hectoretc]

Thanks guys,
Is the transom the consensus location for the through hull port?

Also, for the consumption (information) of anyone who cares, I found this article on the Internet regarding bilge pumps.

http://www.yachtsurvey.com/bilge_pumps.htm

This author thinks that the minimum for a 17 ft boat should be two bilge pumps and gives justifications. I might not have put it high on my "lake sailing" equipment list, but since I received one as a gift, I'll put it to good use and feel slightly more prepared in case of...

[hectoretc]

I screwed the basket to the hull but can remove the upper part of the pump by releasing the plastic prongs.

Hi Jay,
You said you screwed the bilge pump basket to the hull, is that like, "to the hull?" or did you glue in a piece of wood or other material in first?. I know adding anything is going to raise the pump further, and I'm sure the keel is probably pretty thick and a 1/2" screw won't likely break through to water, but I wanted to be sure I understood how you did it before I go ahead and wish later I'd asked.

No rush, I know you're doing the robot doctor thing (that sounds like so much fun). I can wire and plumb the discharge hose at any point. Securing the pump to the hull is just something I just need to do before... I guess before I seal in the battery boxes to the cuddy sole in the spring.

Thanks - Scott

[jdoorly]

Scott, Now that I think about it I remember putting a glob of epoxy on the head of a flathead machine screw and sticking it to the hull. The basket sits on top and is held by a nut in the basket, so I only lost 1/8" of height at most. Hopefully, even on a bad day, I wouldn't screw into the hull! Though, I have installed depth and speed thru-hulls (with 3M 5200)!

Everybody seems to think 5200 to too permanent, can someone suggest something specific to use in its place?

[GreenLake]

Everybody seems to think 5200 to too permanent, can someone suggest something specific to use in its place?

Epoxy!

Actually, it would depend. For bedding deck hardware that's held in place by bolts, for example, butyl tape.

There may be places where the 4200 ?? series would give better results. (You'd have to look that up yourself - I've not had to use any of this).

If you use 5200 and have it in a location where it's possible to "saw" it with a wire, then it might not be "too permanent". But if you can't use mechanical means at all, then you should consider, given the apparent longevity of these boats (yey!) whether you'd want to resort to something that's not practical to disassemble.

People with bigger boats have a wider array of challenging bedding/bonding/sealing jobs. If I had a particular application in mind, I would look into their forums to see what they recommend.

[jdoorly]

Here's the 3M marine catalog. See pp 93-97 to pick a sealant:

http://multimedia.3m.com/mws/mediawebserver?mwsId=SSSSSu7zK1fslxtUNx_BoY_Uev7qe17zHvTSevTSeSSSSSS--&fn=MarineAftermarketCat.pdf

[hectoretc]

For bedding deck hardware that's held in place by bolts, for example, butyl tape..

OK, I've looked and haven't found butyl tape. When I first saw the reference, it thought it was the stuff plumbers use (essentially rolled up plumber's putty) but haven't seen anything to support that initial guess.

So where does butyl tape come from, other than boats, what is it used for, and/or where is it found?

Thanks

[Alan]

Adobe Reader is being persnickety tonight, so I couldn't get jdoorly's link or any other PDF to load. In the meantime, I found this chart of 3M marine sealants at Jamestown Distributors:

http://www.boatbuilding.net/article.pl? ... ode=thread

[GreenLake]

There was an extensive discussion of butyl tape, with sources, on the SailingAnarchy forum (in the FixItAnarchy subforum). Google should find that easily.

[csrguth]

Anyone have pictures of an installed bilge pump?

[Breakin Wind]

Anyone have pictures of an installed bilge pump?

"Almost"... I guess I never actually took a picture of the bilge pump itself, but you can see the drain hose and guess-t-mate where it sits under the cuddy floor.



You can see the hose coming in from the left under the cooler box to a through-the-hull drain in the upper port side of the transom. The pump is attached to the bottom of the boat by gluing a small 1/2 inch long SS machine screw to the hull, snapping off the blue filter cover,



put the screw through one of the filter slots with a washer and nut, and then snap the pump onto the cover to hold it in place (as originally suggested by jdoorly). I have a float switch set about 2-3 inches off the hull bottom so it pumps out automatically if the bilge ever vgets too full when unattended (or when I set sail with the bilge drain plug out) and a manual panel switch to completely pump it out before sailing etc. My grandson likes to flip on the switch and watch my boat relieve itself into the lake. "Your boat had to pee bad didn't it papa?"

This from rainwater that collects in the cockpit, and then drains into the bilge intentionally through a removable floor plug to dispose of back into the lake (via the pump). The two holes in the topmost picture are where my battery boxes have been installed and sealed in place. I started with the advantage/disadvantage of having a huge crack in my cuddy floor in that area, compliments of the previous owner, so cutting out the floor wasn't an emotional decision line I needed to cross. The dual batteries add weight, but its low in the boat, so it helps with stability, and with two batteries and a selector switch, I can run my trolling motor around my entire lake if needed on one battery, and always know I have 100% backup capacity in case I need to do it someday against high opposing winds.



Barring the mental will (or need) to hack holes in your cuddy floor, you can accomplish essentially the same thing working through the bilge access ports in the cockpit floor, but it's definitely harder to do with just one hand, and feeding the hose where it needs to go will give you serious wrist cramps. I'll try to see if I can angle my camera in from one of those access ports to get a picture.

Thanks - Scott