Blowing down the ballast

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Javboat
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Blowing down the ballast

Post by Javboat »

Hi All,

I’ve been searching the forum and found some comments on “blowing down the ballast” when back at the boat ramp and before recovering the boat onto the trailer.

I want to have the ballast in while manoeuvring around the marina and up to the pontoon but then want the ballast out to aid in recovery onto the trailer(ie. I can’t remove ballast with forward momentum)

Can someone explain the steps to blowing the ballast out with one of those mattress / air bed inflators. I tried it last time and stopped blowing air once there was bubbles starting to come out of the main ballast drain on the transom (wife turned the air pump off as I closed the valve at this point) when I got the boat on the trailer and up the ramp a little to open the valve, there was still a large amount of ballast water or board.

Better than explaining, does anyone have a YouTube video of the process?

Cheers,
Chris
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kurz
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Re: Blowing down the ballast

Post by kurz »

Hi Chris
Can't help do drop ballast other than motoring it out.

BUT: Why do you want to carry around the ballast in the Marina just before loading on the trailer?
When you have the daggerboard down or at least half down the :macm: is ok for manoeuvring in the marina.
When I have to load the :macm: on the trailer on the home ramp it is so narrow and on top there is some current, maybe even more some wind.

So I let down the daggerboard half and pull it up just the last 2-4 meteres bevore touching the trailer. I dont think ballast water would help...
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Jimmyt
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Re: Blowing down the ballast

Post by Jimmyt »

If you aren't motoring with the bow up, I don't think you'll get all of the water out. I usually drain mine first during a planing run up river. I have loaded it with ballast though, and I don't notice much difference - other than having to crawl up the ramp while draining. The ramp I typically use is plenty steep and deep, so I can sink the trailer enough to float the boat on - even with ballast full. With the bow level, or down, you will likely be left with quite a bit of ballast using a pressure evacuation method.
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Tomfoolery
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Re: Blowing down the ballast

Post by Tomfoolery »

My marina has a super steep ramp, and it really helps to remove the ballast first so I don't have to dunk the trailer as far. The goal posts already are completely under, and I've extended them. I even added a bow roller to help jump the bow up into the small vee bunk in the front without putting the trailer so deep that the goal posts no longer do any good. It seems to handle well enough with partial centerboard down and at least one rudder full down.

But I have a swing CB and if I forget to lift it, it'll just swing up on its own. I even added a separate carpeted CB support so it doesn't get hooked on the middle vee bunk if/when I do the Mac Bump.

But when I load it with ballast in, which is most of the time away from home, I simply open the vent and the ballast valve, then load it. The instant the bow is raised above its normal level, which happens when it hits the roller and little carpeted vee bunk at the bow, the water starts draining. By the time I've climbed over the bow and down the trailer ladder, hooked the winch line, winched it into the vee bumper, climbed back up and taken the OB out of gear, shut it down and tilt it, raise the rudder and CB, climbed back forward and down the ladder and walked to the driver seat, pulled it forward a little, walked back and winched it again (due to geometry, it pulls away as the trailer bunk to hull angle closes coming up the ramp), and so on, most of the ballast is out by the time the stern is high and dry and it only takes a minute or so to drain the rest while I walk around it "inspecting" (to waste a little time when folks are waiting).

The trailer isn't taking any extra weight to speak of with the stern floating while it's draining, but it's angled nice and steep so it drains fast enough that I don't really have to wait. But even if it did, you won't hurt it. Those wheels, bearings, springs, and frame take a lot more load hitting bumps at highway speed, or even at slow speed over speed bumps, than the extra load from ballast water, climbing slowly up the ramp to drain. And unlike people, holding a heavy load for some time is no worse for a trailer than rapid application and removal.
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NiceAft
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Re: Blowing down the ballast

Post by NiceAft »

Javboat,

Don’t let a little water left over in the ballast bother you. No matter what efforts you make to void the ballast, there will be something left over. I’m sure it’s not enough to place a strain on the tow beast. When you pull off, just keep the ballast wide open, and whatever is left will exit.

When I pull my :macm: out, I try to void as much of the ballast as possible, close the stern valve, and then the vent under the “V” berth. I then run her up onto the submerged trailer. Once on the trailer, I open both valve’s. Whatever comes back in isn’t enough to effect pulling out. As I pull out slowly, the ballast will empty. When the stern is out of the water, I stop for a moment to let residual water out, and then proceed to pull the boat out.

If you use a blower to void the ballast, fine. Just don’t worrry about what remains. You have already removed the majority of the weight. Just pull out slowly, and let the rest empty.

Ray

P.S. When Nice Aft was brand new, the first time I pulled her out I did not empty the ballast until the trailer was fully on the ramp. When I opened the valve, it was like a dam burst. Some old salt watching, told me my boat was too new for that much water to be in the bilge :D
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Re: Blowing down the ballast

Post by 1st Sail »

I agree unless there are special circumstance like a very steep ramp I would load with ballast in. You certainly can load ballast empty but then you have a clorox bottle to deal with. I always have a cross current, wind and waves from channel traffic so load ballast in. By the time I'm up the ramp the ballast is starting to empty. I don't think it takes more than 3-4 minutes to drain the ballast on the ramp.
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Re: Blowing down the ballast

Post by Javboat »

Thanks all, very helpful info from everyone. Slowly learning more about my :macm: and enjoying the process :D
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NiceAft
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Re: Blowing down the ballast

Post by NiceAft »

Chris,

What year is your Mac, and where are you located?

Most of us place that info in the “Profile” section of the “User Control Panel”.

Ray
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Re: Blowing down the ballast

Post by Javboat »

Hi Ray, I’ve just updated that, thanks for the tip :wink:
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Todd
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Re: Blowing down the ballast

Post by Todd »

On the 26M you should have a 12v lighter plug up front. Those 12v pumps for blowing up water inflatables work perfect for blowing the ballast. However you still only get a portion out. I do not know which eliminates more water between blowing it out or using the siphon method from the manual where you motor slowly with the vent and gate open. If I had to guess I would go with motoring as the most effective.
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Re: Blowing down the ballast

Post by dive4it »

I'm reading everyone's replies and still didn't answer his question. I use a high volume inflator to drain my ballast tank at the dock sometimes and the key is to put a rubber bushing on the blower nozzle so it creates a good seal on your air vent (if you don't have the hose extension) and Only open your transom valve about 1/4 of the way open once the majority of the water is blown out Simple physics, water weighs more than air. It'll blow it down to just a few gallons left as long as the bow isn't lower than the vent.

JT
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Re: Blowing down the ballast

Post by Russ »

dive4it wrote:I'm reading everyone's replies and still didn't answer his question. I use a high volume inflator to drain my ballast tank at the dock sometimes and the key is to put a rubber bushing on the blower nozzle so it creates a good seal on your air vent (if you don't have the hose extension) and Only open your transom valve about 1/4 of the way open once the majority of the water is blown out Simple physics, water weighs more than air. It'll blow it down to just a few gallons left as long as the bow isn't lower than the vent.

JT
Interesting. Makes sense. A full open (LARGE) valve would allow water to come back in when the air is blowing out. Yet if you opened it a little bit, it would force water out as air fills.

Great comment.

--Russ
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Re: Blowing down the ballast

Post by Ponaldpe »

dive4it wrote:I'm reading everyone's replies and still didn't answer his question. I use a high volume inflator to drain my ballast tank at the dock sometimes and the key is to put a rubber bushing on the blower nozzle so it creates a good seal on your air vent (if you don't have the hose extension) and Only open your transom valve about 1/4 of the way open once the majority of the water is blown out Simple physics, water weighs more than air. It'll blow it down to just a few gallons left as long as the bow isn't lower than the vent.

JT

That is pretty much how I do mine, I have the inflator plumed in with a ball valve. Open the valve turn on the inflator pump open the ballast valve all the way make sure it makes bubbles then keep closing it till all the water is gone. My main reason was I can empty the ballast for a grounding. It works I have not grounded since I mad the mod. I did empty the ballast once with the blower and loaded the boat on the trailer and opened ballast valve and only a couple gallons came out.
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Re: Blowing down the ballast

Post by Javboat »

Thanks JT, that makes sense. I will do that next time.
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