water ballast over filling??

doehunter · Jul 10, 2011

quality tyme said:
woke up on the boat this morning with water on the floor. further investigation revealed water coming out the ballast site hole. Pumped out the bilge and removed as much weight, including ourselves, and the water stopped flowing out the hole. Either water is entering ballast tank through the ballast valve, bad seal, or a crack below water line in ballast tank. Seems odd that 4 people and some gear would put enough weight to lower the boat and raise the water line to cause this. Anyone else experience this and what did you find out?? :cry:
Forgot to add!!
I have a 26s 1990

My 26S is usually lightly loaded and the water comes up to just barely under the top at the air vent. I think if I had enough load to raise the water line by 3" it would definitely be over the ballast tank. If that happened the vent plug would let water in if it doesn't make a 100 % seal.
That's one good reason to add a piece like Sumner has on his vent. A stand pipe that effectively raises the top of the ballast tank well over the water line.
The valve on the bottom of the boat should not matter. You should be able to leave it open if you wish. The top of the tank is supposed to be above the water line.

Robspan · Jul 10, 2011

doehunter said:
The top of the tank is supposed to be above the water line.

Doe, did you mean that the top of the raised area, where the valve screw and the air vent are located, is supposed to be above the waterline? Because, and I'm subject to correction on this, I think the actual top of the ballast tank is below the waterline when the tank is full. But whether it is or not, if there's a leak in the tank itself, there should be water in the bilge regardless of load.

If there's a leak only when the boat's loaded, then as you say, I would look at the valve seal or the vent seal on the raised area. But the sink through hull or scupper drain could also be underwater under those circumstances as well.

Paul Brinkley · Jul 10, 2011

I would want a good seal on the fill valve (top and bottom) as well as the vent plug. You don't want water overflowing into the boat, and you don't want your ballast to leak out, either. If you can't adjust your vent plug to stop leaking, get a new one, or if needed repair the fiberglass hole so you can seal to it. Check your valve seals, top and bottom, and replace if you have leaks. Blue Water Yachts will have the parts. -Pau

MrBill_FLL · Jul 10, 2011

do you have a water tank? that and a few coolers and a weeks groceries can do it.

I added some thickened epoxy, then tapped the vent hole with steel pipe then use a nylon fitting and some hose. works for me.

I think this is Walt's boat, with a dam to keep any leaks contained.

I think someone just screwed a PVC ball valve in to raise it 3"

check the big rubber washer too. ace hardware had them.

GL!

Mike B1026 · Jul 10, 2011

Water level/ballast tank vent.

I believe you are wrong. Whenever I fill my ballast, it always stops even if I leave my intake valve open. Usually I have to put my finger in to feel the water. Mine has a fair amount of junk I have added but it still doesn't seem to need an "extension." Of course if it was heeled over, water would run over.

It wouldn't make any sense for the top vent to be below the water line. Boats would constantly be getting flooded.

Robspan said:
Doe, did you mean that the top of the raised area, where the valve screw and the air vent are located, is supposed to be above the waterline? Because, and I'm subject to correction on this, I think the actual top of the ballast tank is below the waterline when the tank is full. But whether it is or not, if there's a leak in the tank itself, there should be water in the bilge regardless of load.

If there's a leak only when the boat's loaded, then as you say, I would look at the valve seal or the vent seal on the raised area. But the sink through hull or scupper drain could also be underwater under those circumstances as well.

MrBill_FLL · Jul 11, 2011

Mike B1026 said:
I believe you are wrong. Whenever I fill my ballast, it always stops even if I leave my intake valve open. Usually I have to put my finger in to feel the water. Mine has a fair amount of junk I have added but it still doesn't seem to need an "extension." Of course if it was heeled over, water would run over.

It wouldn't make any sense for the top vent to be below the water line. Boats would constantly be getting flooded.

You don't have enough junk in the boat to lower the waterline.... Yet.

not hard to do, especially if you installed a 30 gallon water tank, coolers, 20 gal fuel, etc...

doehunter · Jul 11, 2011

Robspan said:
Doe, did you mean that the top of the raised area, where the valve screw and the air vent are located, is supposed to be above the waterline? Because, and I'm subject to correction on this, I think the actual top of the ballast tank is below the waterline when the tank is full. But whether it is or not, if there's a leak in the tank itself, there should be water in the bilge regardless of load.

If there's a leak only when the boat's loaded, then as you say, I would look at the valve seal or the vent seal on the raised area. But the sink through hull or scupper drain could also be underwater under those circumstances as well.

Yea,
I believe the boat was designed to have the very top of the tank, where the air vent, and water valve stem are located to be above the waterline.
In my boat, the water will stop filling when it gets to just under the air vent hole. If the boat gets bumped, or if there is wave action, some will spill into the bilge.
In my earlier post I wasn't suggesting that he go out with a bad valve, I was just saying that even if the valve was left open, the boat shouldn't fill up and sink. Assuming it's level all the time which it wouldn't be when sailing.
Jim

Sumner · Jul 11, 2011

quality tyme said:
..If the ballast valve is left open, won't the ballast water syphon out the same as pulling your plug out on an open fishing boat when it fills with water for draing?? You do not need aloty of speed to do this just forward motion. Anyone ever check?

That isn't going to happen on an S or D as you can't get enough speed and I would think that the ballast inlet is too low anyway. I do believe that the X and M guys can remove their ballast at speed.

I wouldn't be too concerned if there was a small leakage at the inlet gasket, especially if you fill the tank on the trailer as then there would be a 'head' of pressure on the valve since there is a depth of water over it.

It isn't hard for the 2 upper gaskets to seal as there is almost no water pressure their since there is no 'head' at the waterline. I got new upper and lower gaskets from BWY for our boat.

We also had a slight amount of water under the sink that if it would of been worse gone over into the starboard bilge. It came from where tube for the centerboard control line. The upper clear tube is hose clamped onto the fiberglass lower housing, in our case, with a single hose clamp and it wasn't tight. I tightened it and added a second with the screw part clocked 180 deg. from the other one. No more leaks there and since our boat is so loaded the water is always up in the upper clear hose.

Good luck,

Sum

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doehunter · Jul 12, 2011

quality tyme said:
In reading the replys, I should not be too concearned. Check the ballast valve seal on bottom and go from there. I will probably haul her up with full tank and check for leaks, hopefully it just leaks around valve seal. But in theory, if seal is good and no cracks in tank, load of boat should not have any effect on the tank level. The system should be closed to any changes in water line level. Only if more water can get in should water in tank rise. I'll keep my fingers crossed and hope it is just the seal.
Heres another Q, regarding Doehunter's thread. If the ballast valve is left open, won't the ballast water syphon out the same as pulling your plug out on an open fishing boat when it fills with water for draing?? You do not need aloty of speed to do this just forward motion. Anyone ever check?

What would happen if you took an empty bucket, turn it upside down, and push it down into the water? Water can't come in if the air inside can't get out. If your air vent has a good seal, it can control the water level in your ballast tank. Water can't come in if air can't get out. Conversely, water can't go out if air can't come in.
With that said, if you were to start with a full ballast tank, leave the bottom valve open, and heel your boat over until the valve comes out of the water, you might have a small amount of exchange. Meaning some water could come out, as air bubbles can come in.
If however, you are sailing and the bottom valve is under water at all times, water can't flow out if the valve is open, unless the top of the ballast tank leaks air. The air leak could be the air vent, the water valve stem seal, or a crack in the fiberglass in the top of the tank.
Wow that was long, Sorry.
Jim