Rplacing floor in my '73 I/O adding ballast?

brian_216 · Newbie Joined: 07 Jun 2006 Posts: 31

Ok I have a 1973 Glasstron V212, here is what its got- a 302 ford, and its strong, changed the prop to a 14 x 19 tops out at 30 but pulls like crazy. and a custom tower. My floor is like a trampoline in some places and I would like to replace it this year.

My question is could I use the cavity below the floor to become fiberglass ballast tanks? I figure since Im tearing the floor up, why not look into it? Im pretty handy with fiberglass and Im thinking if I make lids that will cap off the stringers about an inch below where the floor board will lay and glass them in. I would have to make some holes through the stringers to let the water flow to fill/empty. And run vent lines up and out the sides like where the bilge comes out so I know when they are full. How big? one on each side, and one up front in the center? ( there is no floor storage in this boat either) What kind of pumps would you use? Im also thinking thru hull fittings at the end of each "tank" for hoses to fill and empty. Has this been done before?

wesgardner · Posted: Jul 13, 2006 7:55 am Post subject:

Maybe hasn't been done in that exact boat, but has been done...two thoughts - if using aerator style pumps, they will need to be LOW as they are not self-priming - perhaps you can work in some sort of "pump well" in the middle of things such that they'd be below the waterline... otherwise, if you use the Simer or Jabsco reversing pumps, you can put them most anywhere as they can self-prime...1 inch stuff is generally big enough for single line applications...on my boat (using aerator pumps) my intake thru-hull is 1 1/2" going into a 2" manifold - 4 Tsunami 1200's feed from it...ventlines can be pretty small as they just need to allow "breathing", say 1/2"??

Hope this helps...post-up when you've gone a bit further but as is, your plan sounds very workable..anyway to calculate size of tanks/weight ahead of time?