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I recently installed an "autovent" line on my ballast tank, connecting the forward vent hole through a 3/4" hose to a fitting on the upper edge of the forward wall of the anchor locker.

Now I want to install a water level sensor with a small gauge on the pedestal to tell me when the ballast tank is full and when it is empty so I can properly close the aft valve. Has anyone installed such a valve in their ballast tank? What is the recommended type to use, and where to mount it? I am currently in fresh water, but intend to move to salt water later this summer, so I know corrosion is a potential issue. Any thoughts are greatly appreciated!

Dave Bishop
Southern Star

noone i know of has or would go to this extreme, sounds like your being anal. just look over the back of the transom and look with your eyes,you can easily tell if water is flowing in, out or static. if your a few gallons shy off full it's ok. you just don't want to be 50-60 shy of full.

I believe there was one person who actually added a water level sensor to the ballast tank.

http://www.macgregorsailors.com/forum/v ... or#p219731

Roger

I agree it's over Kill... Filling the ballast is just too simple and I agree with your vent to the anchor locker she will fill quickly.. On the other hand if thats what you want $$ a link was supplied.. That said out of close to 10,000 on the water you'll have 1 of less than 6??? Who have found this a worthy cost, and it is labor intensive to do a proper job..

I may be missing something, but I'm pretty sure the plug in the as-designed ballast tank vent is to significantly slow any leakage past the gate valve. This could be bad as the tank could slowly drain while sailing at good speed. At some point before getting half-way empty, the ballast tank will decrease stability vice increase it as the water sloshes to the low point. Water doesn't come out and flood the compartment in the vent's current location, so I'm not sure what running it up topside gains you. You could achieve the same effect by just leaving the plug out.
When the tank is empty, the plug does the same thing - keeps the tank from changing condition unexpectedly.
I got a clear hard plastic tube to stick down the vent hole. Works pretty good as a Tank Level Indicator. Tank should always be completely full, or completely empty.

A couple more reasons for this:

1) We're planning on making trips this fall with a full cockpit enclosure - so simply looking over the transom becomes problematic.

2) You can't just leave the plug out - there would be significant slop with any motion of the boat that would cause water to come into the cabin from the ballast tank.

3) I don't want to have to go down into the cabin, up to the bow (which we use as storage), move everything around to get to the plug, just to test its level or even to empty/fill. My goal is to be able to do everything from the cockpit - and safely.

Which is why I want to install a level indicator of some sort. I would want to know if the level was decreasing unexpectedly due to a leaky transom valve or any other reason.

Thanks for the input and insight, everyone!

Menkalos:
Leaving the plug out ( as there is a huge IMHO Funnel around the vent) has never allowed any slopping around, for me .. I regularly run my rub rail Very Close to the water..If in fact you have run that vent to the anchor locker? Then there is Zero Issues..
Your Issues:
#1.Full Enclosure trip..? Once you fill the ballast your done..if anything , more will leak in.. I among others had contemplated filling the ballast at the dock with fresh water for a long trip and being able to use some of it for showers dishes cloths etc.. I put mine on the trailer and filled away.. It leaks.. Not a water fall by any means......... but not a solution..
#2. Not That I have ever seen..and I sail mine pretty hard..
#3. Run the vent to the anchor drain Done Deal..
I lived and Worked on the island of Cozumel.. I have installed numerous level sensors several Manufactures.. Unless they have changed a lot they seem to be, IMHO , rather short lived..

I have two ways to monitor the ballast tank after I put in the Autovent:

1. There is a piece of line attached to the top of the
ballast fill hole that gets sucked in when filling then pops back out when the tank is full.



2. I also added a fuel whistler in line of the ballast tank tube so I can here it whitle when it fills and empties.

Erik Hardtle wrote:I have two ways to monitor the ballast tank after I put in the Autovent:

1. There is a piece of line attached to the top of the
ballast fill hole that gets sucked in when filling then pops back out when the tank is full.



2. I also added a fuel whistler in line of the ballast tank tube so I can here it whitle when it fills and empties.

Erik,
Those are both very good ideas. How did you attach the line on hte inside? Do you have any pictures of the installed whistle?

Thanks,
Pedro

The line is attached on the outside of the fill hole with vinyl tape wrapped around the circumference.

Here is the only picture of the whistler device, it shows the one on the fuel line (left) and then later I added another oneto the ballast tube (right). This picture was taken before I put on the hose clamps.

I love the whistle idea. Do you know if it whistles in both directions? It appears that in the fuel loading scenario, you would only care if it whistles in one direction, where in the ballast tank scenario, I'd like it to whistle both ways so I know when it is done filling OR emptying.

Both Directions... (drives my kids nuts)

If I were to install such an indicator, it would be a micropressure switch attached to a NMEA2000 sender relaying information to my Garmin 441s. If i were to install such an indicator...

There are external tank level senders that can be attached to the outside of the ballast tank with no penetrations or anything else to be made. And they're cheap: $35 or so.

http://www.newprovidencemarine.com/product_sensor.html

To put them on an NMEA2K network you would attach them to an analog sender adapter and then calibrate.

Matt

Erik,
That whisttle is a great idea. I have not done the passive auto ballast mod because I would not be able to easily check the state of the ballast. This would also remind you if you forget to close the gate or if there are any leaks. One more mod to the list…

Sea Wind