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All the recent posts about the ballast tank valve replacement, making sure the tank is completely full, and installing an LED indicator to show that the tank is full has got me thinking about a possible winter project.

Has anyone thought of fabricating a ballast tank valve that includes a clamshell scoop that can be lowered below the waterline to refill the tank while under way? The benefit is that the faster you go, the faster the tank would fill. This would allow fast filling while powering away from weather and allow me to switch to sailing much quicker.

I'm envisioning a valve similar to the operation of the factory model with one addtional mode. When fully up, the valve would be fully open as it is now. In the center position, the valve would be fully closed. When fully down, the valve would be fully open, but a clamshell scoop would lower into the water to speed filling.

Something like the thrust reversers on a jet engine.

Have to dream up some projects to keep my sanity while the boat's out of the water for the season.

Bob Cameron

Hey, Bob, check THIS out... look down the page and you'll find this pic:


Your post joggled my mind... I knew I'd seen something similar before... so I looked and found it on the net again. Not my boat, but this guy Roger Brown has lots of nifty ideas for mods.

The valve is open when I launch the boat. By the time I get back from parking the truck, the tank is full. How much faster do you need it to be, and why? You're gonna be sailing. Hurry up so you can go slow?

The Windara solution is only for those of us wil the older 26X boats that have the 2nd valve under the steps. All the late model boats don't have this.

I love the engineering mentality on this board but once in a while I have to give you some grief.

Couldn't we modify the mast to make it fly. You could get away from that storm or get to port much faster.

I was thinking of something along these lines:



Of course it would be nice to get a device to force water out of the ballast faster so it would be a quick conversion from sail to flight.

Have to agree with Chip on this one. Just don't see a lot of need for a quicker fill. Plus that scoop thing is going to add drag and resistance to your forward movement. I keep picturing the motor motoring along and the water gushing out the vent when the tank fills. You'd have to either leave the plug in (tightly), get good at anticipating when it's almost full so you can slow down, or do a lot of mopping. On top of those problems, how would you ever dump it at sea? You'd have to be able to rotate the cup thing aft otherwise you'd never get rid of it. Seems like a really bad idea all around to me.

That's one advantage of the old boats with the two valves. The windara design would let you fill faster. It gives a flush fit on the bottom for better performance when closed. The aft valve is not modified so you can still dump under power just like in the normal setup. Add a vent plumbed overboard and you are set. Just watch the vent and when it is spilling water you are full.

Ah, they laughed and said man would never fly! I like the Windara solution. The issue is not whether the tank fills fast enough when you launch the boat or lack of stability at sea when the tank is empty. Now that I sail on inland waters, I often motor with the tank empty. It's the transition back to sailing mode that I'm addressing. Also, there is a lot of algae and other grunge around the dock, so it is preferable to fill the tank before entering the marina to prevent it from entering the tank.

As for the vent issue, I addressed that years ago by adding a 90 degree elbow to the vent hole under the step (I have a 96X) and leading a hose to a thru-hull high on the starboard side. It is high enough that there is no possibility of the tank emptying through it except in a knockdown. So an overfill condition would only force water overboard through the thru-hull. The LED tank full indicator covered in another post on the board would let me know when to close the clamshell.

The only problem a have with the under-hull solution is that I was planning to seal that hole permanently and increase the rear valve from 3 inches to 4, as with newer models. With the vent extension, I never go below to check the water level or open the other valve.

I'm looking for a solution to incorporate in the valve at the stern.

You naysayers might consider extending the vent hose to a position behind the pedestal. That way a squirt up the pantleg would indicate a full tank. Just kidding!

Seriously, with the way I use the boat, I think it would be a good addition. When I sailed Tampa Bay and the Gulf of Mexico, I would not have considered it, so I know its not for everyone.

Bob

How about installing an impellor on the inside of the transom valve?

Flick a switch - power fill.

Reverse it - power empty.

(more the size of the smaller one)

Spirit of the Wind wrote:Ah, they laughed and said man would never fly! ... When I sailed Tampa Bay and the Gulf of Mexico, I would not have considered it, so I know its not for everyone.

I understand why others might not 'get it' but I do empathize with your frustration.

I motor at speed with ballast empty about 3 miles to reach SF Bay. I prefer not to dally at end of the shipping channel for filling ballast, so once on the Bay proper I'm faced with filling ballast in somewhat roily conditions. It's about the most uncomfortable 6 or 7 minutes of the day to remain stable and stationary on the Bay while the tank fills.

Our solution is to maintain just the slightest forward motion at 1 knot or so just to help damp the rock'n roll of the waves. After adding my passive ballast vent hose, I once posted here that I would try a slow power-reverse to help overfill the tank, but I've never felt that it's too effective. Besides, it's quite a trick to keep that barndoor stern headed square in reverse.

You suggested dropping a scoop or baffle below the transom to force water into the tank. In addition to it's complexity, I doubt how effective that would be, but it might be easy to prototype with a couple of PVC elbows. I really think your best answer will be upsizing to the larger aft valve. That six or seven minutes is just time enough to prepare for hoisting sails.

Well, I must say I've not yet been in enough of a hurry to fill the ballast rapidly... I just open it and wait a bit with an iced tea...

However - and maybe I'm just being way to lazy and simple minded here - but if you're really in a hurry to fill the tanks and transition from motoring to sailing, why can't you just open the vent, open the fill valve, and then just motor in reverse for a little bit? I should think the backward motion combined with the prop wash should do quite a good job of filling it rapidly... or am I wrong here?

kmclemore wrote:Well, I must say I've not yet been in enough of a hurry to fill the ballast rapidly... I just open it and wait a bit with an iced tea...

However - and maybe I'm just being way to lazy and simple minded here - but if you're really in a hurry to fill the tanks and transition from motoring to sailing, why can't you just open the vent, open the fill valve, and then just motor in reverse for a little bit? I should think the backward motion combined with the prop wash should do quite a good job of filling it rapidly... or am I wrong here?

You just don't get it! Simply powering slowly in reverse is not nearly as cool as a sophisticated MOD!

--Mike

Spirit of the Wind wrote:I like the Windara solution.

You keep using the word solution which to me implies there is a problem to be solved. But I'm at a loss to find the problem? You are trying to cut down on the 5-6 minute fill time?

Frank C wrote:You suggested dropping a scoop or baffle below the transom to force water into the tank.... it might be easy to prototype with a couple of PVC elbows....

Actually, I've had a brain-f*rt here... many of you have a ballast valve handle extension... why not just turn that into a method for dropping a u-shaped pipe into the incoming stream under the boat? Then when retracted it would be up against the rear of the transom and out of the drag-envelope? I don't have any sophisticated drawing tools here at work, but how's this for a quick sketch?



(Only problem, of course... is how do you then DRAIN the tank? Hmmm... I'll have to think on this one... perhaps a different arrangement for the end so it pivots front to back, depending on fill/drain?)

I'm having visions of Wile E. Coyote drawing up elaborate plans to catch the Road Runner.

While I have not yet encountered a situation where I felt I needed to fill the tank quicker, EMPTYING the tank is another story. While I wouldn't put it at the top of my list of abilities I wish my boat had, it would be nice to be able to, if needed, just push a button to empty the tank.

--Mike