Do older aluminum boats have the same issues with waterlogged foam?

Beagleville

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I just don't read/hear about foam issues with aluminum boats; is there a difference with the foam in older aluminum boats as opposed to fiberglass?
 

jbcurt00

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Some had same foam, some had different.

You just haven't read all the waterlogged foam alumimum boat topics
 
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flashback

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I'm just rambling and have no facts about it but my thoughts are any foam in a boat has a good chance of getting soaked no matter what the hull is made of.
 

roscoe

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Some of my oldest boats, 1950's and 60's, had seal aluminum tank under the seats. The held nothing but air, but provided enough buoyancy to keep the hull afloat.

Other aluminum boats from the 60's and 70's, had foam under the seats, but open to the air with 4 to 6" of space between the foam and the hull.

1 other boats of mine had foam under the floor, sheets of styrofoam, which were bone dry after 35 years.

Another one had poured foam under the floor, which trapped and absorbed water.

The key thing to remember, is that everything else under the floor was aluminum, so no rotted stringers.
And the transom wood is well above the wet area.
 

JimS123

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And the transom wood is well above the wet area.
Transoms rot because the boats are sitting out in the elements. My tinny was pristine for 20+ years. Four years in the back yard and the transom was shot.
 

roscoe

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Bad bad Jim. You're supposed to keep the inside of the boat dry.


scolding-granny-picture-id123464166
 

JimS123

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Bad bad Jim. You're supposed to keep the inside of the boat dry.
I gave the boat to my son for his pond. The boat was always rolled over when not in use. The wood that rotted was the on the outside of the transom, just where the motor would mount. Obviously, the inside wood was not exposed and it is still like new.
 

huggyb1972

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It kinda depends on the foam used. The white styrene type that is usually inside the seats on smaller type doesn't have water soaking trouble. The pourable expanding foam usually a yellowish color that's used below deck will eventually soak in water.
 

jbcurt00

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It kinda depends on the foam used. The white styrene type that is usually inside the seats on smaller type doesn't have water soaking trouble. The pourable expanding foam usually a yellowish color that's used below deck will eventually soak in water.
Not correct, the 2nd worst waterlogged foam I experienced in an old tinny was white stryo bead foam, or EPS. Worst was the the pink packing peanuts below a poorly built PT 'deck' w bedliner sprayed on it found in my 1st Starcraft..šŸ¤®

Besides the 'beads' slough off of EPS and can clog limber holes and bilge pumps, poor choice
 
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IMO it's less about the aluminum vs glass as it is how was the boat stored and used during its life. Every boat has a story. Some are epic novels and some are more like a short pop-up book.
 

Texasmark

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I just don't read/hear about foam issues with aluminum boats; is there a difference with the foam in older aluminum boats as opposed to fiberglass?
Back in about 1985 I bought a 1965 Alumacraft 18' Holiday I/O that had been sitting in a marina tied to a dock but the transom area was under water. I restored the boat and used the same white (moldy) Styrofoam bats that were in it originally and had enough structural integrity for me to hold at one end and support the whole sheet without breaking in the middle....about an inch or so thick, just thrown in there before the wooden deck was riveted to the aluminum frame. Testing revealed that they had not absorbed water. Blown in foam, usually open cell can accumulate moisture so I hear.

Fast forward: 2 years ago I bought a 2002 Crestliner Fish Hawk, also aluminum hull. Looking at the blown if foam at the transom it looked like it needed to be replaced and showed signs of fuel discoloration on the surface. I cut off a chunk of it and placed it in a tub of water. It floated like a freshly fallen Oak leaf on a rippling stream.

So, I read that some does and how to test for it. I just haven't had a problem personally.
 

huggyb1972

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Not correct, the 2nd worst waterlogged foam I experienced in an old tinny was white stryo bead foam, or EPS. Worst was the the pink packing peanuts below a poorly built PT 'deck' w bedliner sprayed on it found in my 1st Starcraft..šŸ¤®

Besides the 'beads' slough off of EPS and can clog limber holes and bilge pumps, poor choice
I mean it surely can't be as bad as your making out to be they've been using it to float docks forever. Pink packing peanuts for flotation foam that's a new one. Lol
 

jbcurt00

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I mean it surely can't be as bad as your making out to be they've been using it to float docks forever. Pink packing peanuts for flotation foam that's a new one. Lol
Take a look at some of the Starcraft rebuilds, plenty of nasty foam
 

ahicks

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I did a '93 19' Grumman deck boat with a rotten floor. Purchased "right" as I knew it was going to be a project boat. That boat had VERY water logged poured in foam. A foot square chunk carved out would need both hands to pick up! Just getting that foam removed was quite a project as it had to be cut from anything it was touching...
 

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roscoe

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I gave the boat to my son for his pond. The boat was always rolled over when not in use. The wood that rotted was the on the outside of the transom, just where the motor would mount. Obviously, the inside wood was not exposed and it is still like new.
Well they obviously didn't soak that wood in enough toxic waste before installing it on the boat.

Dad, then I, owned a 1959 Meyers 12'er for over 50 years.
On the trailer all summer, upside down behind the garage all winter.
Never had it covered.
Foam was dry and all transom wood was solid when I gave it to a friend for his pond in 2012. The wood was soaked in something red. Whatever it was, it will probably kill me some day.
 
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