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Bow Ballast - Rough draft/final copy hopefully!!


Ndawg12

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You'll probably get a suggestion from others about using a 1200 GPH pump over an 800. I have no experience with either yet, so I can't officially comment on that. Looks good though. Are you pumbing a new intake hole, or Y fitting an existing?

Edited by CrazyTegger
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You'll probably get a suggestion from others about using a 1200 GPH pump over an 800. I have no experience with either yet, so I can't officially comment on that. Looks good though. Are you pumbing a new intake hole, or Y fitting an existing?

I plan to just use the existing drain, but I use that the most of all the plugs, so now I'm second guessing that, thanks!!! Tease2.gif

As for the pumps, I'm never in a hurry out there and I think my max capacity will only be half the bag (300+- lbs). I think I calculated it to around 7-8 minutes fill and drain.

Edited by nemire12
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Exactly the same set up as I have. It works great. I also purchased a factory bow ballast switch cover from Bakes Online.

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Couple of things:

1. I would put a loop in the drain line.

2. Don't worry about a 1200 vs. 800. An 800 will plug right in & on a bag that size it won't make a huge difference vs. trying to make a 1200 work with the system (you'll need multiple reducers/increasers :)). Stay with the 800, you'll be waiting on the middle tank anyway.

3. Is there a reason for the 90 between the water pickup & the pump? If possible, I'd eliminate that. The 800 should screw right in to the ball valve.

4. Venting?

5. Are you using an existing thru hull for the pickup or drilling a new one?

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Couple of things:

1. I would put a loop in the drain line.

2. Don't worry about a 1200 vs. 800. An 800 will plug right in & on a bag that size it won't make a huge difference vs. trying to make a 1200 work with the system (you'll need multiple reducers/increasers :)). Stay with the 800, you'll be waiting on the middle tank anyway.

3. Is there a reason for the 90 between the water pickup & the pump? If possible, I'd eliminate that. The 800 should screw right in to the ball valve.

4. Venting?

5. Are you using an existing thru hull for the pickup or drilling a new one?

1. Got it.

2. That's what I was thinking.

3. I think I'll be getting to tall so I'll turn it to run parallel.

4. Venting, I've heard you don't need to vent a sack, apparently you disagree??

5. You gave me the link for the thru hull fitting that I'm using. Thumbup.gif

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4. Well, it's all a matter of opinion. I like mine vented, that way I don't have to worry at all about a possible rupture resulting from overfilling or too much pressure on the bag. Whatever floats your boat though. :)

5. Actually I meant at the water pickup. Are you using an existing plug?

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4. Well, it's all a matter of opinion. I like mine vented, that way I don't have to worry at all about a possible rupture resulting from overfilling or too much pressure on the bag. Whatever floats your boat though. :)

5. Actually I meant at the water pickup. Are you using an existing plug?

4. Ha!! I hear these bags are pretty tough, plus I will be "semi" enclosing them. Won't the over filling pressure just go past the drain pump and ou the drain. Am I missing something or are you just a little on the ....how should I word this :unsure: ....worry wort side? :)

5. You're the second person to ask me that, and now I'm really pondering it. I was planning to use existing but I use that plug the most!!! I guess since the drill is out I could just put 2 holes in the boat!!

Edit: Another hole might make it easier to route everything around the bilge pump..??

Edited by nemire12
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4. I'm a self-professed Worry Wart. Double & triple redundancy is a thing of beauty to me. :lol: Seriously though, the bags are pretty tough so I don't think that's much of an issue. One thing that you could run into though is the buildup of air over time, & the need to "burp" the sack to get it full. A vent will almost completely eliminate that need, provided that the vent is in the right spot.

5. Use the existing plug. The reason I say that is that anytime you drill into the hull that far forward, you run a big risk of messing up water flow over things like your paddlewheel. I cannot emphasize enough how important this point is. Clean water flow over the paddlewheel is the single biggest factor to its performance, that was why I asked. If you're using an existing plug, then this isn't a factor, but if not then placement of the new plug is very important.

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4. I'm not trying to argue, I've actually heard that "burping" concept in other threads as well, but it doesn't make sense to me. As the water comes in, it seems like it would push out any air through the drain followed by the water when it's full.....ah wait a second (we need an emoticon with a lightbulb that turns on above his head) it fills from the top and drains from the bottom so the air is trapped up top and then prematurely pushes the water out without being totally full. Duh.. ok now I'm totally sold on venting, I'll have to figure out the best way to vent this thing, any suggestions?

5. good I hate drilling, the smell of fear smells exactly like drilled fiberglass, I hate that smell.

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4. I'm not trying to argue, I've actually heard that "burping" concept in other threads as well, but it doesn't make sense to me. As the water comes in, it seems like it would push out any air through the drain followed by the water when it's full.....ah wait a second (we need an emoticon with a lightbulb that turns on above his head) it fills from the top and drains from the bottom so the air is trapped up top and then prematurely pushes the water out without being totally full. Duh.. ok now I'm totally sold on venting, I'll have to figure out the best way to vent this thing, any suggestions?

5. good I hate drilling, the smell of fear smells exactly like drilled fiberglass, I hate that smell.

Often there's 2 fill plugs on a lot of bags. One could act as a vent, providing you only run one intake

Edited by CrazyTegger
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4. I'm not trying to argue, I've actually heard that "burping" concept in other threads as well, but it doesn't make sense to me. As the water comes in, it seems like it would push out any air through the drain followed by the water when it's full.....ah wait a second (we need an emoticon with a lightbulb that turns on above his head) it fills from the top and drains from the bottom so the air is trapped up top and then prematurely pushes the water out without being totally full. Duh.. ok now I'm totally sold on venting, I'll have to figure out the best way to vent this thing, any suggestions?

5. good I hate drilling, the smell of fear smells exactly like drilled fiberglass, I hate that smell.

Often there's 2 fill plugs on a lot of bags. One could act as a vent, providing you only run one intake

So I assume that I run the vent over to the drain with a "Y" fitting..?? Is there any reason to put a check valve on the vent line???

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martinarcher

I don't have my sacs vented, and use the fill pump to prime the drain pumps since they are below deck. When I see a good flow of water out the drain thru hull I shut her down. We do need to burp the bags pretty often though since like you said the drain is lower than the fill and air can get trapped in the bag.

I had an idea for using a hydronic(water base board) heating air/water separation valve to bleed the air out of the top of the bag, but haven't tried it yet - I'll have to let you guys know if it works. I hate to run another stupid hose just for a vent! For those who haven't seen them they allow air out and keep water in.

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There are 2 ways that you can vent.

1. The simplest, most straightforward way is to drill a second thru-hull (for the black fitting that I gave you the link to) & run a line to the third valve on your bag. Easy, simple, straightforward, & the best method IMO for burping a bag (other than manually that is).

2. The other way is a little harder to explain. Basically you want to put a y-fitting on the fill line, with the vent coming off of the the second prong of the y going to a thru-hull of its own. The y has to be oriented against the flow of the water to avoid the stream "splitting" at the y, if that makes sense. What this does is to push water out of that second prong of the y when pressure reaches a certain point. It doesn't work as well at burping as #1 though, but if you orient the y correctly, it can have the secondary side benefit of acting as a siphon-prevention measure. This works as an option for people with bags that only have 2 valves instead of 3.

Either way, you'll have to drill a second hole for the black thru-hull. If you plumb it into the drain line with a y, you'll need a check valve on both lines, which introduces restriction. It's simpler to just put another thru-hull IMO.

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this wye fitting I'm looking at states that it does not allow one line to pass through to the other.

wye

How is the "burping" method actually performed?

Edited by nemire12
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As water in the bag rises, it displaces the air inside of the bag. Now, if you have a "sealed" system, the air can't escape because it's at the top, & water is getting pushed out the bottom through the empty pump/line. (I use the word "sealed" sort of tongue in cheek, because really there's no such thing in a ballast system. Air will build up over time in any of these systems, so it comes down to how you want to deal with that.) So, IMO the best way to burp the bag is to use the third valve on the bag & plumb in a vent line. If you use the y that you linked to & plumb that into the empty line close to the thru hull, you should be golden.

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Looks good to me. The only other thing is that I would try if at all possible to eliminate that 90 degree elbow between the fill pump & ball valve. You may be right that there isn't enough room, but you never know. I would hate to see you run into prime difficulties.

When you're done, would you post some pictures? I'm curious to see how that bag works in that boat. I'm seriously considering an older VLX or Vride for the next boat & this would be one of the first projects on the list. :)

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Looks good to me. The only other thing is that I would try if at all possible to eliminate that 90 degree elbow between the fill pump & ball valve. You may be right that there isn't enough room, but you never know. I would hate to see you run into prime difficulties.

When you're done, would you post some pictures? I'm curious to see how that bag works in that boat. I'm seriously considering an older VLX or Vride for the next boat & this would be one of the first projects on the list. :)

I will definately measure it but I really doubt it will fit.

I will absolutely post pics of the install process and performance results. I like to be proactive, I am "nickel and diming" this project so I probably won't do the actual install for a few months, but I've all ready got a few parts so maybe it will be sooner.

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is that on top of the cushions?

No sir, it will be under the seats. My idea is this: place the bag and fill it with air to see how far the arms actually reach, then cut 3 peices of some kind of water resistant board, carpet them, some how I will attach them to the under side of the seating frame, then finish it off with 2 end caps that will go at the end of the arms.

I realize this is wasted space when the bag is not filled but it's a trade off I'm willing to make to not have to worry about the seats raising up when the bag is filled. Plus it should look pretty good with it being carpeted and I might still have a little space for storage in there.

Does anyone know how much room is left at the ends of the arms??

Here's a rough sketch of what I'm thinking about doing.

post-8316-1247142774_thumb.jpg

Edited by nemire12
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