Bilge Hose Valve

[imported_74baja]

Hi all,
I was tinkering around the boat (1974 16' Baja speedboat with 155 Johnson) and I noticed that the previous owner had failed to seal the bilge pump through-hull (white plastic 3/4") at all when he installed it. I had been wondering where water leakage was coming from, since the new engine and battery the boat sits a little lower in the back, and if its docked and I am moving around, the through-hull scould eeasily be right near the waterline. So, I plan to seal the through-hull with caulking. However, I also noticed that if water could enter the through hull, it could travel down the hose to the bilge. Then I had siphon nightmares. So, is there any kind of one-way valve I could install along the hose (3/4" white ribbed plastic)? This is not the first "no duh" boating folly I have discovered from the past owner. I spent 6 months two winters ago replacing the transom because he did not have sleeves in the splashwell drains and did not seal the motor mount holes.
Thanks,
Jack

 

[DJ]

Re: Bilge Hose Valve

What you thinking of is called a "sea ****".

You can see examples here:

http://www.iboats.com/Marine_Store/dm/*******.043422423--keywords.sea%20cocks--search_type.keyword--**********.589159822--submit%2Ex.29--submit%2Ey.11

If it were me, I'd seal the hole and move it up. You may also consider moving the battery forward.

 

[imported_74baja]

Re: Bilge Hose Valve

I thought about sea cocks, but then I thought that the best for me might be some sort of flapper valve that I could put in the hose. The bilge hole would really only be near the water line occasionally. I had also thought about moving the battery, especially because it is on the same side as the bilgo thru-hull. It has had quite an effect on the boat since the old battery was aobut half the weight. it is about 60-70# and since it sits all the way to the rear starboard side, when the boat is docked, it tilts slightly to starboard. I do not have much room elsewhere for it, but I thought about one the floor right under the dash, but then I was worried about whether it might have trouble with porpoising or just getting on plane with two people in the front plus the battery. Any thoughts?

 

[DJ]

Re: Bilge Hose Valve

You're not going to have issues getting on plane with a 155 HP engine. If you do, you have other issues. Besides, "porpoising" is caused (mostly) by too much weight aft (rear).

Move the bilge pump outlet. That "sometimes" can sink your boat.

If you do move the battery, you'll need a minimum of 6-guage cable(s).

 

[imported_74baja]

Re: Bilge Hose Valve

Whoops, meant to say 115 hp engine not 155.
Thanks for the adivce. I am starting to think that I have a pretty big too much weight in the aft problem, because I can't really move the hole up, it is only about 1" below the rubrail. I think I will move the battery and see exactly how close to the water line the hole is, and if it is still too close I'll have to move the hole foreward or something... what a pain, it'll look terrible if I have to glass over the old hole from behind. Unless I just left the current thru-hull in but sealed it fromt he back and plugged it, and installed a new one a fooot or two forward?

 

[DJ]

Re: Bilge Hose Valve

Unless I just left the current thru-hull in but sealed it fromt he back and plugged it, and installed a new one a fooot or two forward?

There you go. Shove a wine cork in it (from the inside) sealed with a little 3M-5200. Nobody but me, you and 100,000 + iboaters will ever know.

 

[External Combustion]

Re: Bilge Hose Valve

This one is easy. "One way valves" are simple ordinary check valves. Installation is a no brainer.

All through hull fittings should have a seacock mounted immediately inside the hull to prevent disaster. You should also keep a wooden tapered plug on board at all times that would fit the hole in the through hull fitting in case the seacock becomes damaged. The plug takes up almost no room and is far better than an explination in Admiralty court.

Right after the seacock, a simple check valve will solve your problem. I like the "flapper" or "gravity" style as they have lower flow restriction than the spring style.

On my steam launch I have my bilge pumps routed so they have to go through two check valves before they exhaust below the water line. Regulations specify that the boiler must drain below the water and the bilge pumps use the same through hull fitting. The upside is that every hour I check out the watertightness of the check valves. I have yet to have a leak in all of these years.

If you use a check valve, and I reccommend one, use one pipe size larger than the bilge pump hose. This reduces the back pressure on your pump. Since you have a 3/4 hose from your pump, use an one inch check valve.

They are easily found at the big box stores. Get the all brass type and use brass hose barbs. If you sail in salt water don't worry as the valves are really bronze and the hose barbs can be ordred in bronze also.

Place the valve so you can get to them easily. This allows you to take them apart while you are underway (see the need for seacocks now?) and clear out any junk that might clog the valve.

If they ever leak, then you will notice it as the pump will run more frequently or the water will rise slowly if the through hull fitting is under water. Don't fret. Remember mine is under water all of the time and I have had no problems.

No need to relocate your through hull fitting.

 

[Boatin Bob]

Re: Bilge Hose Valve

I'm not a fan of putting any kind of valve in a bilge pump line as they can get stuck with debris. I think the easiest fix to your problem is to get a longer piece of bilge pump hose and put a little loop in it above the thru hull fitting. This way the pump can still pump the water out and if water should come in from the outside it won't tavel up the loop. Have seen this work very effectively on many boats.

 

[imported_74baja]

Re: Bilge Hose Valve

Bob,
I don't know if this is a logical fear, but i thought about the loop idea, or just routing the hose higher, but then I had worries about siphoning if for some reason one would start. I think I will move the battery (I had been wanting to anyway) and install a check valve right away, then re-assess. I don't really want to put a seacock on unless I absolutely need to because this is an old, small speedboat and the part of the hull that the bilge outlet is through is about 1/4" of fiberglass. I suppose I could glass on some 3/4" plywood and cut the outlet hole through it to give me something to screw the seacock fasteners into.
Thanks for input,
Jack