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John How
04-11-2013, 05:12 PM
This space is just in front of the transom and will be isolated from the bilge. There will be a motor well and other stuff here. I plan to run two of these drain pipes and valves on either side of the keelson from the bilge out thru the transom. All epoxied in place so that they can be opened after the boat is on the trailer and still on the launch ramp to drain any collected water. What do you think?

http://www.johnhowguitars.com/images/MargieLou/transom%20drain%20idea.jpg

John B
04-11-2013, 05:26 PM
John, I think if will be below the WL then they should be treated as through hulls and should be of marine quality. Above the WL, trailer boat ,not sure ,but my gut says the same.

JimConlin
04-11-2013, 05:27 PM
I'm not sure that I understand the details, but I would not rely on a bond to PVC In a thru-hull situation.

pamelalynne1
04-11-2013, 06:02 PM
I do not understand your reasoning for separating this area from the bilge. All water should be directed toward the transom through which you would install one or two drain plugs. You can purchase one inch plugs and brass sleeves for the drains, drill the holes through the transom, epoxy the holes and the outside of the sleeves and insert the sleeves in the holes. Once it is cured you just install the drain plug. You really should have easy access to this area. If you've already sealed this off from the bilge area, have you cut limbers in the frames and battens to allow the bilge water to drain toward the keelson? If not, you need to direct the flow of the water in order to eliminate pockets of water being trapped and the possiblity of deterioration and rot. If this issue has been resolved, drill through the frame under the bulkhead into the transom area on both sides of the keelson, epoxy brass sleeves in those holes and this will allow the water to drain. From the picture it looks like you will need a drain on each side of the keelson through the transom. I would also install a bilge pump with a float switch on each side in order to dispose of water while underway. If it was my own boat I would open the area and, if desired for aesthetics, install a hatch to close it off.
As was previously stated you do not want to use PVC pipe for this!!!!! PVC and PVC cement does not get along very well with petroleum products and is not intended to withstand the vibration and pounding the hull will certainly experience.

Breakaway
04-11-2013, 06:03 PM
I would use stiff hose, maybe like sanitation hose, not pipe. Rigid tubing/pipe, over time, may compromise the seal at the fittings as the boat works/flexes/ages/,etc. Use a short length of pipe/tube as a nipple at either end for your scupper and discharge.( Though purpose made scuppers and through-hulls with barbed stems are probably better, but must be bought)

Kevin

wizbang 13
04-11-2013, 06:07 PM
yup , like exhaust hose
but i am not sure of the boat type

Figment
04-11-2013, 06:33 PM
My mako has a hard-piped plastic drain like that for the live well. It sucks. It's #2 on the list of things to rework.

John How
04-11-2013, 09:57 PM
Actually water should never should get into the bilge (never say never cross fingers) unless holed or something. The boat will be decked and the cockpit completely sealed. The cabin companion way is above the sheer as well but it seems prudent to allow for drainage just in case. The area in front of the transom was intended to be closed for flotation and storage so will be accessible via a round hatch cover but I don't really want water running thru it if I can help it. I could just put a pair of thru hull with plugs in the garboards I guess. The cockpit not being high enough to be self bailing will have a manual pump and I will probably put one in the bilge as well. The boat will be stored on a trailer and under a roof when not in the water so rain is not really an issue while in storage. Boat in question, Margie/Lou (http://sailboatforme.blogspot.com/).

pamelalynne1
04-12-2013, 06:48 AM
Actually water should never should get into the bilge (never say never cross fingers) unless holed or something. The boat will be decked and the cockpit completely sealed. The cabin companion way is above the sheer as well but it seems prudent to allow for drainage just in case. The area in front of the transom was intended to be closed for flotation and storage so will be accessible via a round hatch cover but I don't really want water running thru it if I can help it. I could just put a pair of thru hull with plugs in the garboards I guess. The cockpit not being high enough to be self bailing will have a manual pump and I will probably put one in the bilge as well. The boat will be stored on a trailer and under a roof when not in the water so rain is not really an issue while in storage. Boat in question, Margie/Lou (http://sailboatforme.blogspot.com/).

Unless you have a sealed, self-draining deck or a full cabin it is inevitable that, at some point, you will have water in the bilge, either from spray, hull damage or rain when underway or when the boat is uncovered at the dock. I remember many times racing a shower to shore and running to the nearest shelter to keep dry. Often there would be several of us standing on a covered porch waiting for the rain to stop. You could also develop a leak in a mooring cover while you have the boat docked or moored for any period of time. I install adequate limbers/scuppers, bilge pumps and drains in every boat that I build as does any manufacturer of any type of boat.

Ian McColgin
04-12-2013, 07:01 AM
Planing motor boats commonly have a transom drain that can be plugged at will and opened when either running at speed or on the trailor. This general notion is a good way to keep the inevitable bits of gasoline that appear in the motor well from contaminating the whole bilge. Since minimizing the number of holes and being able to drain the well area are both goals, I'd flush up the area on either side of the keelson both in the area shown and in the main bilge just ahead of the bulkhead. That way you could have one tube leading back through and out, and another transom hole to drain that well only.

I'd absolutely not use rigid PVC pipe. Put in proper thru-hulls. If the access is really good, you could probably use typical motor boat bilge plugs for both outlets. This would allow the hole to get closer to the bottom of the boat than a seacock would.

G'luck

Breakaway
04-12-2013, 07:17 AM
Actually water should never should get into the bilge (never say never cross fingers) unless holed or something.

Water can accumulate due to condensation ( cool hull, sun beats down on topsides). But, you are trailer stowing, not wet stowing, the boat.

But Ian's logic makes sense to me, even for a dry-stored boat.

Kevin

pamelalynne1
04-12-2013, 08:08 AM
Planing motor boats commonly have a transom drain that can be plugged at will and opened when either running at speed or on the trailor. This general notion is a good way to keep the inevitable bits of gasoline that appear in the motor well from contaminating the whole bilge. Since minimizing the number of holes and being able to drain the well area are both goals, I'd flush up the area on either side of the keelson both in the area shown and in the main bilge just ahead of the bulkhead. That way you could have one tube leading back through and out, and another transom hole to drain that well only.

I'd absolutely not use rigid PVC pipe. Put in proper thru-hulls. If the access is really good, you could probably use typical motor boat bilge plugs for both outlets. This would allow the hole to get closer to the bottom of the boat than a seacock would.

G'luck

Full agreement with Ian here. Just remember to flush up the area between each bilge batten with wedge shaped pieces so the water will naturally drain to one point and epoxy them to the bottom to seal out moisture. At the expense of being accused of overkill, you could overlay the wedges with fibreglass tape or woven roving. You want all the water to drain to the lowest point where you will put your drain plug. If you do this properly you will also only need one bulge pump at that lowest point.
I guess we've beaten this topic to death LOL

outofthenorm
04-12-2013, 10:50 AM
Actually water should never should get into the bilge ....

LOL. No offense, but that`s hilarious.

- Norm

John How
04-12-2013, 11:02 AM
LOL. No offense, but that`s hilarious.
- Norm

Of course it is, which is why it'll have pumps...