Water ballast vent

[Dutch01527]

Next mod on the list is a ballast tank vent. I do not like the idea of leaving the helm and going up to the v berth to open/close the vent when sailing alone. I would also like to be able to close the vent when full, not sure this is really necessary but it was designed that way for a reason presumably .

I have seen the vent mods suggested on here but none seem ideal. Would the following work:

- tap and secure straight (thread to hose) connector into existing hole
- run vent pipe back along bilge to cockpit pedestal with first bit of hose looped high to prevent water getting in
- connect stainless water tank filler fitting to pedestal and to hose
- drill another hole at v berth ballast tank and fit water level float gauge
- run cable along bilge back to water level gauge on pedestal

I think that would enable venting the tank by unscrewing the filler cap, seal the tank by replacing the filler cap and monitor the water level all from the cockpit.

Any thoughts?

[yukonbob]

IMO I'd put any money considered for this mod into an autopilot to man the helm while down in the V for the 10-20 seconds it takes to fill. If you open the gate valve and let the bulk of the water "glug" its way in until it slows you only need to go under the V to vent for 10-20 seconds to top up the tank. I usually just put it in neutral and bob around for a few min, also grab something to drink maybe a snack while I'm down there then go back up and motor or sail on.

[Dutch01527]

Given my current rate of spend on the boat best not mention expensive mods such as Autopilot, it might just set me off on something else I just must have

[boatbitch]

I cut the bowl off, ran the vent line to the forward drain for the anchor locker. No need to close it off if vented to outside the boat. In this high place it is unlikely to leak any ballasts water.

[BOAT]

I do everything from the helm:



It's hard to see from the above picture but there is a selector switch on the helm to open and closed the bow vent:



The bow bent has a big 1-1/4 inch brass motor operated ball valve venting the bowl connected to a equally large 1-1/4 inch reinforced hose that vents into the chain locker.



I prefer venting the top of a sealed bowl because it will still work without leaking even if the hose comes loose.

I recommend a large hose so that the tank will empty faster when underway, (after all, the whole point of working from the helm is to empty (and fill) the tank when underway), the larger size hose allows for the air to flow faster. I would not cut off the bowl if I were you as it's designed to keep the ballast water in the tank in case the hose, valve, or plug fails and also serves as a visual inspection for the ballast level. You can see in the picture above there is salt water spray inside the glass window - that was after sailing in rough swells and water sloshes in the bowl in heavy seas - therefore the bowl is a good thing to have in case the plug or hose fails or you will get water in your boat.

[Dutch01527]

Boat

That is a very elegant bit of engineering, how do you check the tank is full?

[BOAT]

Boat

That is a very elegant bit of engineering, how do you check the tank is full?

That is the next step Dutch - I need to install a float switch in the bowl so it will send a signal to the helm when water in the bowl floats the switch (when 'boat' is full I usually get about 1 inch of water in the bowl).

Right now I can look through the glass and see the water in there but the whole point is to eliminate the need to go forward. I am still shopping around for a float switch.

[seahouse]

Boat

That is a very elegant bit of engineering, how do you check the tank is full?

That is the next step Dutch - I need to install a float switch in the bowl so it will send a signal to the helm when water in the bowl floats the switch (when 'boat' is full I usually get about 1 inch of water in the bowl).

Right now I can look through the glass and see the water in there but the whole point is to eliminate the need to go forward. I am still shopping around for a float switch.

https://www.amazon.ca/Glentronics-BWD-H ... sensor/url

Or wire something like one of these (you can probably find one for US$10) with a helm switch and two electrodes (9V stuff works off 12V if you wanted to do away with the 9V battery, not to mention that if your wire run is long enough and of fine enough wire that you might end up with 9V anyway from the IR drop) at the top of the bowl. Use nuts and bolts that got through the cover, easy to waterproof, and connect the wires to them.

In salt water the distance between the electrodes can probably be farther than on the original device, if it needed to be.

Do a "marine conversion" of the electronics by opening it up and spraying the circuit board with silicone, or similar, spray.

When the alarm stays on continuously... it's full. You could check that it's full at any time by flipping the switch on and off.

-B.

On edit: use an appropriate amount of tape over the siren to reach the desired volume if it is too loud.

[BOAT]

I was looking at those kind of options but kurtz made a ballast tank indicator for his boat that used a gas tank sender so that made me think about it more to see if I thought a sender was a good idea.

The idea of a sender that tells me the actual level of the water in the tank was something I wanted to thoroughly dismiss before I installed a switch and regretted it. You should have noticed by now that it takes me MONTHS to figure out designs in my head that you guys usually figure out in a few hours. I'm just slow that way.

The sender intrigued me because on a long voyage it would show a dropping level if I had an aft valve leak or something. The idea of actually seeing the level go down while under power was also a novel idea to me but not so sure it was worth the hassle.

This is still banging around in my head. (the head between my ears - not the head between the dinette and the bow berth).

I was looking at these too:



But right now I am leaning in the direction of this kind of thing:





http://www.maretron.com/products/tankMonitoring.php

P.S. After remembering my own thoughts on this project I must say I made a stupid post because now I remember why I was not in such a hurry to rig a sender on the ballast tank - as you recall those of us that had our tanks vented to the anchor locker all had a hose going right from the tank vent hole to the chain locker like this:



And the only reaal reason for a tank sender was because the hose blocks your view of the water inside the tank. When i changed over to sealing the bowl and putting the hose on top of a glass window that solved that issue. I never ran up front to check the tank level and I still don't now - but I guess if I just had to know the level without going forward I could pout in a sender but I think in my case this will probably never happen unless I decide I need to cross the pacific ocean or something - highly unlikely.

[Retcoastie]

No need to vent when emptying. Think of a soda bottle or a can. They empty quite well without a vent. The difference between vented and unvented is maybe thirty seconds. Once the fluid gets below the top of the gate valve there is room for the tank to vent thru the open gate valve.

[dlandersson]

Hmm.... I would have thought that they empty much more easily/quickly WITH a vent.

No need to vent when emptying. Think of a soda bottle or a can. They empty quite well without a vent. The difference between vented and unvented is maybe thirty seconds. Once the fluid gets below the top of the gate valve there is room for the tank to vent thru the open gate valve.

[BOAT]

He is pretty much right: If you are pulling it out of the water on the launch ramp it does empty out pretty fast because of the two channels in the upper part of the rear ballast section.

If you are trying to empty the tank while under way by moving forward under power it does take a lot longer with the vent closed.

It's filling the tank that is a real bear without a vent hole - the water just goes Glug, Glug, Glug, Glug, and it takes FOREVER to fill up.

One of the main reasons i put the forward vent on an electric valve was so I could just drop the motor, pull the handle and go - I just turn the switch to OPEN and the water rushes out.

[Retcoastie]

Hmm.... I would have thought that they empty much more easily/quickly WITH a vent.

Don't think so. I have pulled her out on the trailer with the ballast still in. When I pull the gate valve, she burbles and gurgles for a very short period and then water runs out evenly. As soon as the water level gets below the top of the gate valve opening, air starts going in the gate valve opening and from that point on a vent is totally useless.

If it is 45 seconds per empty, I don't think I'll have our Mac long enough and empty enough times to offset the hours required to install some type of permanent vent system, not to mention the beer money used unwisely.

[BOAT]

Yes, technically you do not need a bow vent at all - you can just let the tank fill up and empty out just from the back but it will be VERY VERY slow to fill up and very very SLOW to empty when underway.

If time is beer money then your going to spend about and extra 20 minutes in beer money filling your tank and even more time in beer money emptying it out on the water.

[dlandersson]

It may be the model year - my 98 takes far more than 45 seconds to empty with the vent closed.

Hmm.... I would have thought that they empty much more easily/quickly WITH a vent.

Don't think so. I have pulled her out on the trailer with the ballast still in. When I pull the gate valve, she burbles and gurgles for a very short period and then water runs out evenly. As soon as the water level gets below the top of the gate valve opening, air starts going in the gate valve opening and from that point on a vent is totally useless.

If it is 45 seconds per empty, I don't think I'll have our Mac long enough and empty enough times to offset the hours required to install some type of permanent vent system, not to mention the beer money used unwisely.