here is the start to my 21V ballast install

[Pro-Fab]

I am using 4 attwood tsunami 800 GPH pumps and 2 rule 1100gph pumps (because I have them already)
Using 1.25" thru hull, and 3 dpdt carling switches, 1" fill and drain hose, 2 500 lb sacks in the rear and 400 lb sack up front.

I still need to get all my thru hulls, clamps, and hose. And for picture purposes I can't leave it out.

http://i25.photobucket.com/albums/c69/mr2turbo7/48233f4f.jpg

I have all the bags and two more pumps in the boat.

[Pro-Fab]

would it be terrible to not put a vent in? if there is no air in the bags then I dont se the problem with running an air tight system.

[Pro-Fab]

I recieved the rest of my ballast parts from mike last Thursday, I completed my ballast install in about 4 hours 30 minutes of which was trembling over drilling a 1 1/4" hole in the bottom of our boat. We are using a 400 lb bag for a bow filler so I used extra hose for the front ballast so that I can run the front bag any where in the boat. This can really help add weight in the rear corners for surfing when we only have 3-4 people on the boat. I did not end up using the drain thru hull for the fron as I will just run a hose long enough to throw over the rail for draining, and if we dont use it as much as I anticipate in the rear then I will eventually run the drain thru hull up front.

I will post pictures over the weekend. I need to make a plate to mount the switches because the PO mounted a sattelite radio reciever in the indent above the speedo adjustment knob.

We left out Friday Evening after I finished the ballast install. I had no leaks and the ballast works great except the rear bags still had about 1-2gallons in them.

[laserfish]

Pics please. Would love to see where you mounted the thru hull and drains. I know that trembling feeling from the installation of the Perfect Pass paddle wheel. Measured 20 times and was still really nervous with that hole saw.

[lohe]

Any updates with pics? :)

[Pro-Fab]

sorry I had somewhat of a short season last year. We started going to the dunes with some friends and also had a drop in business so funds were not there. expectto make a LOT of trips this year. I will post updated pics of the ballast install. here is a picture of the plate I made for the switches today. I useda piece of 22 gauge aluminum sheet. I cut the holes for the switches using a dremel and my small home made sheet metal brake to bend the aluminum. as well as some tin snips to cut out the sheet.

First I used a piece of paper to make a template and then traced my desired template onto the sheet metal, then cut it out, and did some fine tuning with the tin snips and brake. trilled the holes and riveted the plate on.

http://i25.photobucket.com/albums/c69/mr2turbo7/2011-03-07_15-45-55_704.jpg

[WABoating]

30 minutes of which was trembling over drilling a 1 1/4" hole in the bottom of our boat.

Man, I totally understand that feeling. I'm getting ready to install my ballast system this Spring and the number one worst part will be drilling the intake holes in the hull. I've drilled through fiberglass to install a waketower, and that was bad enough, and it was still above the waterline. Actually drilling several big holes in the absolute BOTTOM of the hull just creeps me out.

[Pro-Fab]

sorry no pics, I had to reseal my oil pan on the cummins, and put a new tranny pan gasket in.

[Pro-Fab]

ok so here are the rest of the pics from the ballast install.
valve and intake (starboard side of v drive)
http://i25.photobucket.com/albums/c69/mr2turbo7/intakeandvalve.jpg
manifold (starboard side of transmission)
http://i25.photobucket.com/albums/c69/mr2turbo7/manifold1.jpg
port side locker
http://i25.photobucket.com/albums/c69/mr2turbo7/portlocker.jpg
Starboard locker
http://i25.photobucket.com/albums/c69/mr2turbo7/starboardlocker.jpg
front sack under helm but is placed in either bow or rear seat
http://i25.photobucket.com/albums/c69/mr2turbo7/helm.jpg
drivers seat with switches
http://i25.photobucket.com/albums/c69/mr2turbo7/placeable.jpg

[Pro-Fab]

going to plumb the front sack drain before season hoepfully and wire drain switch for front sack as well as wire the lights in the switches up.

Notice the manifold is twisted slightly downward so that when water fills the manifold it automatically feeds the pumps and doesnot allow cavitation to occur when pumps are on.

[WABoating]

Notice the manifold is twisted slightly downward so that when water fills the manifold it automatically feeds the pumps and doesnot allow cavitation to occur when pumps are on.

Actually, you normally want the flow to be "continuously uphill" from the bottom of the hull to the pumps if you're using aerator pumps. If any section of the inlet plumbing is higher than the pumps, an air bubble will not be able to escape and will block water flow to the pumps. If the plumbing is "continuously uphill", though, any bubble will propagate up to and escape through the pumps and then water will be available at the pump's inlet.

When you drop your boat in the water, there is air in the inlet plumbing. The water will start to force its way up, but if there's a "trap" as I've described you can end up with no flow.

Impeller pumps can draw a vacuum, so they are not susceptible to this problem. Aerator pumps do not draw a vacuum so you must be much more careful in how you route the inlet plumbing because the system MUST be self-purging.

Please report back on how this works for you.

[Pro-Fab]

aerator pumps will let water past the pump when they are off because it is a cartridge style pump and not air tight, a ballast puppy pump will not let air past the pump when not on because it is an air tight impeller style pump. That is why the ballast puppy has enough suction to draw water through the line.

The cartridge style pumps will cavitate if there is air. the pumps being angled down in such a manner will help the pumps fill with water because the pumps are below the water level. They will not cavitate because the air is forced up through the cartridge. just the same for placing your drain pumps on the bottom port in the sack, the waters weight will force the water into the drain pump, and keep it from cavitating. if you over fill a bag with aerator style pump the watter will push through the drain pump and out the drain if there is no vent.

I have used this ballast many times last year (hundreds if not thousands of fills and empties) and never once had an issue with cavitation.

also if there is a small air pocketit will be higher than the pumps allowing the pumps to suck water and begin a syphoning effect.

[WABoating]

I'm not worried about cavitation. I'm worried about an air bubble sitting at the top of the inlet plumbing. Water pressure or "weight" is not going to force such a bubble down and out. The aerator pump isn't going to draw a vacuum, so that won't evacuate a bubble either.

The fact that an aerator pump will pass air when not running has nothing to do with this problem. It's entirely because the inlet plumbing runs higher than the inlet of the pump.

If you're not having problems, you're lucky. If you ever do, this is the first place to check. I would have arranged those pumps so their bodies were above the manifold, not below, but that's just me.

[dom w. forte]

I agree the pumps should be standing straight up , they will have a hard time primeing because of an air bubble in the manifold, we have boats that the outlet hose on a straight up pump wont prime because of the hose getting a droop and acting like a sink trap , everything has to run uphill including the bag vent to let the air out of bladder.

[Pro-Fab]

seeing as how the pumps are under the water line significantly, the water will fill the pumps. They are slightly turned down and not completely upside down. We tested the manifold and the water line of the boat and determined that the water pushed most of the air out of the manifold. The cartridge will stay full of water allowing it to continue sucking water. if and when the air is pushed towards the pump the air will be pushed through the pump by the water, period. If the pumps were placed on top of the manifold they would be so close to the water line that if we were in a choppy water setting it COULD prevent the pumps from continuous pumping. The pumps were angled down so that there is ALWAYS water in the pump as the entire manifold is under water unless we are jumping or something crazy, in which case we would not need to be filling ballast.
Trust me this manifold/pump set up was tested before it was installed. waterline measurements were made and this is how she tested best.
Basically for our application this was the best method. think of it this way. if you have an air bubble trapped at a high spot you do not want that high spot to be the pump. also think that the lowest part of the manifold is the pump cartridge, and the outlets ares facing upwards. If, for some reason, an air pocket gets to the cartridge the air will simply float past the cartridge to a higher point.

There has not been a problem with this set up and nor will there be.

[WABoating]

if you have an air bubble trapped at a high spot you do not want that high spot to be the pump.

Actually, that's exactly what you DO want. As long as the pump's inlet is below the waterline, you DO want air to escape upward toward the pump.

Just being below the waterline does not guarantee no air bubbles. Don't believe me? Imagine this: A piece of hose, or assembled pipe and fittings, that is U-shaped. Hold the U upside down. The assembly will be full of air. Now lower it into the water. What happens to the air in the pipe? It goes to the highest point - where there is no outlet.

Now, imagine tilting that assembly to one side. Some air will escape but until you rotate it such that one outlet is the highest point in the assembly you will always have some trapped air.

This situation does not change just because there's a pump on one end. As long as there is a "high spot" in your inlet manifold you run the risk of a trapped bubble preventing air from reaching the pump inlet. And since these are aerator pumps, they cannot draw a vacuum and cannot force-purge the inlet plumbing. You are entirely dependent upon passive purging, which works due to buoyancy, which is sensitive to the highest point in the system.

I'm glad you haven't had any problems. I hope you never do. But someday....

[dom w. forte]

All I can say is we have had a lot of problems with MC and CC and 2007 and 2008 tiges and it was always due to the pumps being lower then the feed and even when the feeds were correct the hose comeing off of the pumps once used several times would keep water in the line and cause the hose to droop , once it droops the air gets trapped in the pump and wont prime, and once the vent gets water trapped in the hose it wont vent causeing the pump to over work.
Next time you run the system check and see fill time, and see if it meets pump specs per tank size, I would be currious.
Im not saying your system wont work I just believe its going to work harder, and periodically not prime.

[Pro-Fab]

the pumps are lower than the hoses can droop for each pump. I guess there is always a possibility of air in any system. but like I previously stated if any air is trapped it will be above the pumps and water will flow past and iff this water so happens to push the air to the pumps it will flow through the pumps and past them. Fill time is ~2-3 minutes for each rear sack which I believe are actually 750 lb sacks I need to actually measure them.

[dom w. forte]

We never had any problem with the 03 to 06 tiges that had a simular set up to yours, except the pumps were straight up on the manifolds and worked perfect, only problem they had was you couldnt be moving because the pickup was on the transom and would starve the pump if you went to fast.

[WABoating]

there is always a possibility of air in any system. but like I previously stated if any air is trapped it will be above the pumps and water will flow past

That's the exact situation I've been warning about. That would be a bubble trapped in the inlet plumbing above the pump inlet. Think about that upside-down U plumbing example again. When the boat is initially lowered into the water, water will be forced UP into the manifold - but even if the outside water level goes above the top of the manifold the air bubble won't be magically forced DOWN and through the pumps.

I get the impression we're not going to convince you of what's really happening. So just keep this in mind and if you have a priming problem, you'll know why. If you ever need to reinstall your manifold and pump system, give serious thought to rearranging things so that the flow is continuously upward from the thruhull to the pumps.

Please remember we're trying to help, not criticize you.

[WABoating]

One more way to visualize it:

If you lowered a drinking straw vertically into the water, the air in the straw would naturally be pushed up and out through the top.

What would you do if you intentionally wanted to trap some air in that straw, while leaving it open on both ends? You could add a bend or loop in the middle such that the straw went up, back down a bit, then back up. Now, when you lower the straw in the water, an air bubble will be trapped at the top of that loop. Indeed, a bubble would remain there even if you completely submerged the straw!

That's the situation you create when you have a manifold above the pump intake.

[Pro-Fab]

Please dont get me wrong, I understand what you guys are saying, and that is the exact reason I did testing before intall, because I had the same worries. I then realized that if I mounted the pumps straight up and down I would have an issue of the pumps being above the water line periodically, specifically while under way or in choppy water, and when angled upwrads seemed to trap air in the pumps fairly frequently, while angling the pumps downward seemed to eliminate priming issues even if there was some air in the manifold because the water would fill the pumps rather than the air. one other thing is that the manifold angles down towards the rear which keeps any bubbles towards the front of the manifold and away from the pumps.

I think another contributing factor is some water is force fed through the intake underway.

I really dont mean to sound like im arguing but I am just stating how I have tested this system and set t up. If I have priming issue, the manifold will be the first place I look. I really do appreciate everyones input.

BUt because I diligently stated my point I am sure the first trip out this year we will have priming issues. if that is the case I will have to configure a new set up that places the pumps lower but I am unaware of how that might be. :)

[WABoating]

if that is the case I will have to configure a new set up that places the pumps lower but I am unaware of how that might be. :)

Not lower. Higher. The problem is that your manifold is above your pumps. I understand you are concerned about the pumps being above the waterline but you solve that by lowering your manifold. Making the pumps even LOWER with respect to the high point in the intake system increases the likelihood of problems.

The pumps need to be as low as possible (to keep their intakes below the waterline) but still at the top of the intake system (so air naturally gets purged out of the intake system, up through the pumps). Trapped air isn't going to flow back down out of the thruhull, so the only place it can get out is through the pump itself. And to insure that, the pump must be the highest point.

one other thing is that the manifold angles down towards the rear which keeps any bubbles towards the front of the manifold and away from the pumps.

But that's precisely what you DON'T want. This arrangement traps air in the manifold system by keeping it "away from the pumps". You want air in the system to rise up to the pumps, because if that happens the reason is because there's 100% water behind it. In your arrangement, any air in the manifold is stuck there and cannot escape. I think you'll agree that in a system intended to pump water, it's best to let any trapped air escape?

[WABoating]

I just thought of something: Are you using a scoop thruhull and not a mushroom? If so, the force of the water being pushed into the manifold while underway might drive air out of the system through the pumps. However, you'll always have that pressure and the aerator pumps will pass it right through to the bags, constantly trying to fill them. You'd mask your purging problem but suffer from no way to stop inflowing water other than shutting off that ball valve.

So... are you using a scoop?

[Pro-Fab]

any through hull on the bottom of the boat will either create a vacuume or force feed water through the system. In our case we are using a mushroom through hull and it does actually autofill very slightly (we really dont mind) this could be why we havent had the problems you are discribing.

The way I interpreted the information deducted from our tests is that consideringthe entire intake/ pump system is under water the amount of water in a 1.25" i.d. pipe the little bit of air that remains will be insignificant and stay at the highest point. And the amount of water that will feed the pumps will keep them running. If the air were to enter the pumps it would escape the pump rather quickly, because of its insignificant quantity.

So far my theory has proven right for our system. The forced induction was uncalculated for but I am certain that it will not hurt our situation.

Im not an engineer by any means but I am a man with more common sense than you could ever put in any homedepot shopping cart. I design things and build them for a living I do measure and calculate everything I build but I like trial and error as my main source of testing, because it allows for real world situations, including miscalculations and unnatural occurences. If this system should ever fail I will fix it in a way that it will last longer than the previous time, because then I could recalculate my miscalculations, and plan for the unnatural occurences.