Another twist on 24ve ballast upgrade

[Zad]

We have a 2007 24ve that we are tweaking to increase weight and we have been trolling this and other sites trying to figure out what to do. Our boat came with factory ballast including two hard tanks along the transom and a bow sac under the front seats. We wanted to maximize the rear lockers and side seats but weren't interested in tearing out the factory ballast (resale, laziness, and an appreciation for how the hard tanks do a pretty good job of utilizing the space back there). Last night I finally got down to it and tore out the rear locker battery and taps enclosures, sat down in the hole and had a gander. I was surprised to see just how much space there was above the hard tanks. In fact, after some measuring, I decided there was enough room on the port side above the tanks to put the batteries. The tank is pretty beefy but I didn't know if it was strong enough to hold the batteries so today I called Tige and one of the tech people figured it would be plenty strong enough. So the plan is to move both batteries to sit on top of the port transom hard tank and move the taps pump on top of the starboard tank. The blower is going to be mounted on one of the stringers glued to the transom. Then I will build out walls for the engine side and transom side of each locker likely using HDPE in 1/2" to 3/4" thickness. This will open up the entire locker for one of Michael's custom sacs while keeping both hard tanks in place.

Here is a photo showing the layout for port side with the engine on the left and the white transom hard tank under two batteries. The battery enclosure and engine wall are removed. We are still working out exactly how we will hold the batteries in place securely but given that the transom is the most stable part of the boat I don't think it will be too hard. In the photo you can see the original battery placement where the trays sit. I will have to organize a bunch of wiring, build two new walls for each locker including a buildout to cover and protect the drain pumps and hoses for the hard tanks. I plan to use HDPE for the walls. At this point we figure we will use velcro between the tanks and battery trays to prevent lateral movement and provide some cushion. Strap the batteries to the trays and also strap the batteries to stringers glued along the transom. Early going yet but I think it will be a good option that maximizes weight and minimizes work. I will post more photos as I go along and if you have any ideas about how to do this better please chime in.

batteries 2.jpg

[Zad]

Night two of the locker mod saw some progress. On the port side we were able to get the battery tray fronts cut down to make it easier for the batteries to be removed when the time comes. I siliconed some backing behind the batteries to stop them from moving forward and back and laid down velcro under the battery trays. Despite the tight space I was able to get all the wires connected without blowing anything and when the transom locker wall is in place the batteries will be held firmly between the wall and the backing. The only way they will move is side to side and that won't happen with the industrial velcro I used. This locker is now ready for walls which we started on by making cardboard cutouts. Tomorrow we will cut the 1/2" exterior grade fir plywood, test fit it and then marine epoxy before temporarily installing before finishing with carpet care of Mike and Liquid Audio. Custom ballast bags are on order from him too. For this year we are going to manually fill the custom bags.

port11.jpgport12.jpgport13.jpg

[Zad]

Now onto the starboard side. First shot shows starboard rear locker with the taps pump and blower having removed the "L" shaped cover. Second pic is looking into the engine bay from the starboard locker. Note the backing attached to the transom as a cable fix point. I screwed a piece of plywood to that backing to give something to mount the blower on. Taps pump then got moved up onto the starboard ballast tank. I have yet to secure that. My plan is to velcro the base and then make a mounting arm that will attach the pump to the backing on the transom. Same plan with walls on this side as port as you can see the cardboard mock up of the engine bay wall.
star11.jpg

[dukesofhazzard]

looks bigger already, nice job

[Ewok]

Nice job thinking inside the box( locker area)! You might need to add an some hose to the blower to the pickup for the blower exhaust fan is as close to the bottom of the bilge as possible. The battery idea is a great one but that plastic tank will flex and break eventually. I know you already did all the work to put the batteries up there but I would have put down a piece of plywood or starboard under the battery trays to try to distribute the weight across the top of the tank and maybe put some legs to it so it's not relying 100% on the tank to hold it there.

[Zad]

Ewok, I had to bail on the idea of putting a thin sheet of plywood under the batteries as there is just not enough room. Just thinking about it now I might see if I can find a piece of plexi-glass, that might be just the ticket to give some support and still be thin enough to allow room to get the wires onto the battery. Might also have to get a battery post attachment to allow me to bolt wires to the post and spread out some of the attachment points. The batteries will be sandwiched between the transom and the rear locker wall so there will be very little rocking motion, if any, which might spare us the tank. I will run it as is for the next little bit until the memory of doing contortion yoga in that back locker fades a bit. And, the walls of those tanks, from what I understand, are pretty thick...it just might be able to take the stress.

I will add some hose to get the blower sucking from the bottom of the bilge.

From what I understand, the floor of the rear lockers on the 07 do not have a cavity beneath them so we are limited to the custom sacs that fill the lockers and under the seats. We also have the bow sac. Given the ballast we will have, how do you think the surf wave will be? And, will we need to add some weight to the opposite from surf side locker in addition to the factory ballast?

[IDBoating]

I will add some hose to get the blower sucking from the bottom of the bilge.

Coast Guard requirement (or it might be AYBC, can't remember now) is that the blower must draw from a level no higher than 1/3rd from the lowest point in the engine compartment. Yours looks high to me in that photo. I'd make certain.

[Zad]

Will do.

[chpthril]

You want a few feet of blower hose? got some in the shop.....

[Dandy]

I agree with EWOK that the weight of the batteries is eventually going to cause damage to the tank. I would go so far as to say there will be damage even if you put some ply under it. Considering that the batteries are more weight per volume (I believe) than what water can provide, why not keep them in place and build a housing around them. I thought at one time, there was mention of Chpthril having a sac available that has a "step" that would sit up over the batteries - or maybe it was stated that a regular sac would fill the space and sit on top of a battery compartment. If that tank fails, that will be a lot of water flooding the area quickly and would possibly allow the battery terminal posts to make contact with something and short. I know this all would be an extreme case of bad luck, just something to consider.

[Zad]

You want a few feet of blower hose? got some in the shop.....

Sure, thanks Mike.

[Zad]

I agree with EWOK that the weight of the batteries is eventually going to cause damage to the tank. I would go so far as to say there will be damage even if you put some ply under it. Considering that the batteries are more weight per volume (I believe) than what water can provide, why not keep them in place and build a housing around them. I thought at one time, there was mention of Chpthril having a sac available that has a "step" that would sit up over the batteries - or maybe it was stated that a regular sac would fill the space and sit on top of a battery compartment. If that tank fails, that will be a lot of water flooding the area quickly and would possibly allow the battery terminal posts to make contact with something and short. I know this all would be an extreme case of bad luck, just something to consider.

I spoke with the tech guy at Tige and he figured the tanks would be ok, being that they are built like brick sh$! houses. We will be the test case and see how it goes. As of now, the plan is to run it for this season and if it survives pull it apart and check for any flex marks or cracking. At that time I will lay down some weight distributing platform, likely plexi-glass.

[IDBoating]

I spoke with the tech guy at Tige and he figured the tanks would be ok, being that they are built like brick sh$! houses. We will be the test case and see how it goes. As of now, the plan is to run it for this season and if it survives pull it apart and check for any flex marks or cracking.

I've got to side with those recommending against relying on those tanks to support the batteries. The stress marks, cracking, etc. is likely to occur on the inside surfaces where you aren't going to see them. Those tanks are subjected to extremes of temperature, mechanical loading and cycling from water going in and out, vibration, etc. When they finally fail, it will be a catastrophic event with lead-acid batteries landing in who-knows-what orientation, perhaps stressing the cables attached to them with the weight of the batteries if there's not enough slack, and so on. And then you get the fun of pulling the unrepairable tanks and either replacing them or completely reinventing your ballast setup. That's not a pretty picture no matter what happens.

This is just my $0.02, YMMV, IMHO, I'm just one guy with less than average intelligence, etc. but I wouldn't do it. Not even with a sheet of unobtainium distributing the weight. You're already saying "...if it survives...." Build a shelf with legs that transfer the load to the floor/hull, or something. Do it right the first time and you'll never have to think about it again.

Please accept this advice in the helpful spirit in which it is offered.

[Zad]

WABoating, of course, advice well taken and appreciated. I will rejig it.

And, WABoating, if I can make this work with the batteries on the tank (stand/platform etc), how will our ballast weight compare with what you have done? What do you run for ballast in the rear locker opposite to surf side?

[Stingreye]

I'm just one guy with less than average intelligence

If this were true..... that means I am a complete idiot


You have done a great job so far but if it were me, I would pull out the tanks and run custom sacs all the way to the wall or make a small cavity for the batteries. Those 250 lb tanks will fill up way faster than any sac you put in the locker so going with a bigger custom sac and pulling the tank allows you to use that fill and drain pump to double up the fill and empty the capacity on the sac.

I don't think leaving the tanks in helps with resale. Many boats had no ballast of that era. I think (and its like just my opinion) that only the under floor tanks would add to resale value. It also don't think it would be that much more work since you are already in there are rebuilding walls as it is.

If you really want to maximize your ballast check out WAboating's battery shelf on the transom in the engine compartment. It will let you get all that space open for sacs.

I do think you are on the right track of going as big as possible. I can't believe how much weight my 24V can take and still feel safe.

Good work and keep up the progress and pics! Especially the wave pics when you are done!