Waterlogged Flotation material?

[unior]

I've got a 69 16 foot glassmaster trihull. I keep hearing horror stories of waterlogged flotation material in older boats. I'm just a little concerned cause my boat drafts so much water. The hull alone drafts about 2 feet of water with 700 lbs in the boat. The boat planes fine with only a 50hp Mercury. The deck is extremely solid. Should I be worrying or no. No water ever has drained from the lower drain hole.

 

[Watermann]

That scum line isn't 2 feet and looks to me in a normal location. I don't know that boats were filled with that expanding pour in foam in the 1960's.

 

[wahlejim]

If you have a 50hp planing easily I wouldn't worry about it. If you are losing sleep over it, its easy enough to drill some exploratory holes and patch them up for peace of mind.

 

[Scott Danforth]

or weigh the boat

if its within 100# of the listed weight.... your good

if its 1000# heavier than the listed weight..... youre carrying water....

 

[Texasmark]

Find a spot where it's exposed and whack off a chunk and put it in a basin of water. If it floats like a leaf sailing across a lagoon in the fall forget about it. I just bought boat I know has been partially underwater for an extended period of time. Just looking at the closed cell, poured in foam it looks horrible. I went to the worst looking area and whacked off a piece. Floated just as I said above.

 

[matt167]

The 1961/1963 Custom Craft sea ray I had, did come with poured foam. It was under the deck poured right around the stringers and there was a box that was built to contain it up in the bow

 

[Texasmark]

The 1961/1963 Custom Craft sea ray I had, did come with poured foam. It was under the deck poured right around the stringers and there was a box that was built to contain it up in the bow

Some time ago USCG or some regulating agency, maybe marine builders association or such said that foam flotation had to float the boat upright. That brought on a lot of the "box" of foam you are talking about. I remember Forrest Wood cutting up one of his Ranger Bass Boats (mid '90 time frame) to show the foam and how well it floated with the side cut out of it.....(course the side cut out kept it from being FULL of water so that was a neat trick! lots of boats had a large chunk on either side of the transom and they took up a lot of space previously used for fuel and batteries.

The 2002 Crestliner I just bought discussed the closed cell pour in foam that they use and it's ability to resist water intrusion. As I said, 17 year old boat, known to be partially swamped at a marina for some length of time, No absorption as I could tell.