What is the purpose of the foam

I have a 1974 Glastron v173. This is a 17' runabout with a Johnson 115 on the back.. There is foam under the floor and also on either side of the outboard behind the two rear seats. I would like to remove some of the foam behind the seats and make a battery tray there. In the center bilge area I would like to install a live well. will this create any problems that a newb like me needs to be aware of? I tried to post a couple of pics but failed several times...Thanks....Bill

Re: What is the purpose of the foam

It is called flotation foam, it is to keep your head above water in case of a catastrophic failure, it will not prevent water from getting in, but it will help keep your boat from sinking.

Re: What is the purpose of the foam

MTboatguy said:

It is called flotation foam, it is to keep your head above water in case of a catastrophic failure, it will not prevent water from getting in, but it will help keep your boat from sinking.

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Ditto. Course you don't need it till you need it!!!!!!

Re: What is the purpose of the foam

Taking that much out I don't think would be a problem as long as you don' pull it all, it also serves a structural part so it is best to leave ti is you can but that little bit shouldn't hurt.

I would use a big butcher knife that way you aren't going to accidently go through the hull like you might with a power tool, it will take a little longer but save time in the long run.

Re: What is the purpose of the foam

The foam is for upright flotation and you will or should find some under the gunwales and deck. There should also be a couple of pieces at the stern, under the floor too.

HOWEVER: The foam back by the transom is encased in a plywood box that is glassed to the floor, transom, and hull sides. On these early Glastrons, the transom plywood does NOT go full length between the sides of the hull because of the odd shape back there. The foam and box--especially the box-- reinforce the transom. Removing the foam and wood box will compromise the rigidity and integrity of the transom.

Yeah, you might be able to "get-away" with removing it, but personally, I would not do it.

That's my 1971 V153 in the avatar. With the foam in place I can fit a battery box and two six gallon tanks and it is much narrower overall than your V173 at the transom. However, I also have a V163 and it is a little smaller internally but I can still fit a built-in tank and battery.

Re: What is the purpose of the foam

This is the purpose of the foam:



I'd rather have this to hold on to till help arrives and possibly be able to tow/salvage it back to shore than have it sink like a rock to the bottom.

Re: What is the purpose of the foam

Ok, thanks, I'll leave the foam in there and place the Batteries under the back seats. I'll just raise the back seats up a little to make room.
I hope I never get to test that foam out...
The boat is rated for a 125 hp motor, I have a 115 on it, so the boat should stay afloat if it fills with water???

Re: What is the purpose of the foam

I don't know about your V173 but I can tell you that once I left the plug out of my V153 for about 1/2 hour and it only got about 2 inches of water above the floor (with a 90 on it). So, I ran it with the plug out to drain the water. Yes, you are not a man or woman until you have left the drain plug out. It is a rite of passage for all boaters.

I did raise the seat boxes on my 153 because it was uncomfortable looking through the windshield. I felt like my butt was dragging through the water. I was always sitting on the seat back to get high enough. Now I fit one six gallon tank under each seat and visibility is very much improved.

Re: What is the purpose of the foam

ezmobee said:

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That's just a boat in stealth mode.