MacGregorSailors.com

I posted this on the 'Lifeboat' while the main site was down but realise many may have not seen it so I apologise now for being a nuisance! I'd like your esteemed engineering thoughts please!

]"My recent posts were to do with getting the ballast out faster and I realise that the 19 only has a 2" ballast (RV waste gate type) valve and a 3/4" vent so whatever I try isn't going to be fast!

I've been thinking about the possibility of adding a draught tube to the valve sticking out of the stern of the boat and letting the tube act as a venturi which will form a vacuum as you motor along and draw the ballast out. Rather like a fluid driven vacuum pump or steam ejector. I've noticed some RIBs have a flexible tube but I don't think that draws a vacuum just act as a non-return valve. Some dinghys also have self bailers which must work on a similar principle.

I have in mind a short, because the valve and motor are on the centre line, plastic tube/spigot, maybe tapered, converging/diverging if that's necessary, fixed to the valve mounting bolts and projecting into the water flow at the back of the boat. May need a bend/swan neck to get the outlet down away from turbulence around the back of the boat?

What do you think? "

Your solution requires forward speed. I went a different way.

We have an inflatable air mattress that came with a battery operated air pump that puts out a lot of volume but not too much pressure. Attach said pump to the vent hole and it will blow the water out. Start with the drain valve open but slowly close it when you start getting bubbles.

This can be done sitting still, which is very helpful if you have run aground or are at the dock/ramp.

Hello Retcoasty,
I like Your idea of blowing out the ballast water. It will save You fuel because this method allows to travel with low rpm and get the tank emtied. I will try it as soon as possible.I was thinking of installing a pump, but if this works it´s much simpler .

While in my Marina Slip, I tried using my 12V hi-volume air blower (a WalMart air mattress unit) to empty my ballast yesterday. The unit spout fits snug into the "X" vent hole, and after turning it on, I opened the ballast valve about half way. A large amount of ballast water flowed out, but after 4 or 5 min., nothing but large amounts of boiling bubbles. (The tank chlorine odor was noted also). It seems that about half the ballast water settles toward the front of the boat, and using air pressure doesnt work completely.

I think it wouldve worked if more weight couldve been set in the cockpit, lowering the aft of the boat, so the ballast water would settle to the back of the tank.

I was surprised at the amount of water the air-blower removed so quickly.

Im still messing around with this idea...

i am using a Coleman (Camping Gas in Europe} rechargable air pump to empty the ballast water on my 1996 X, with partial success (probably due to the fact that the valve was fully opened).
I have changed the rear ballast valve from the standard size to a 3 inch one.
Next time i will try with the ballast valve partially opened.

I too have successfully pumped air in to get the ballast mostly empty. Currently I use a hand pump (actually it is "son come here for a minute") which works fairly well. I am in the process of setting up a 12V air pump for our next trip. I was also thinking of trying the pump in reverse mode to fill the ballast quicker to. I have a 97 Mac with the smaller valve so every little bit helps...

I put the larger gate valve in, It was an easy mod. It really helped both fill and drain times I also moved the vent to the bow compartment to make sure I get the tank completely full. I routed the vent back to the aft end of the galley with a 3/4 inche ball vlave. It will be easy to try the pump idea. The older X's had some problem fully filling because of air trapped in the bow.
Thanks for the idea