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DAULEY
09-10-2004, 07:31 AM
deck off engine out drive and transom assembly off
old tank out
waiting on new tank should be here monday
sanded inside of hull and gelcoted it gray
still no foam
will post pixs tonite

DAULEY
09-10-2004, 09:00 AM
pixs

boatnut
09-11-2004, 02:05 PM
Thanks so much for sharing the experience and the pics.
We are considering the same job. If you have time, would appreciate being able to ask you a few questions:
1) Was the tank obviously leaking or bad or did you just change it based on age? Our tank doesn't show leakage but being a 1969 boat with the history of these tanks we are planning to replace it. How bad was the tank after you removed it?
2) Was the tank aluminum?
3) What tank are you using to replace it?
4)How do you plan to mount it (foam?)?
5) Have you considered installing some flotation in the
boat (e.g. foam, air cells, inner tubes)?
thanks, Ed

DAULEY
09-12-2004, 07:46 AM
tank was leaking when i got boat
tank was steel
i am installing a alum tank . it will be foamed in
at this point it has taken about20 hrs should have tank on monday
engine back in transom assembly back on now the wait for the foam and tank to get here

Tony
09-12-2004, 02:12 PM
boatnut,

Change it NOW...this is almost the offseason, if you have one. It is very likely leaking, but the fumes/liquid gas just hasn't made it out of the foam yet. That is what I decifered after just going thru this on my '67. Kind of like "CSI, Michigan". My foam was wringing wet down in the stern bottom side of my 38 year old steel tank, but the top couple inches of foam was dry due to evaporation. In my case, gas finally started oozing out the drain tube on the front side of the tank bulkhead. As others advised me...it is too serious a problem to put off. You do NOT want to go boom!

My brother and I had over 100 hours involved, partly because you'll find several other things to do while the deck is off.

Thanks to everyone who helped me...simply by participating on this board. Again, this is an example of me tackling this project mostly because of the confidence I have in obtaining solid advise from our members.

Here's my links, there will be a final one soon, I hope!
http://www.donzi.net/forums/showthread.php?t=35831&highlight=Deck-off
http://www.donzi.net/forums/showthread.php?t=36114&highlight=Deck-off
http://www.donzi.net/forums/showthread.php?t=36402&highlight=Deck-off
http://www.donzi.net/forums/showthread.php?t=36558&highlight=Deck-off

Tony
09-12-2004, 02:33 PM
Dauley you are giving me some DEJA VU!

DAULEY
09-12-2004, 03:39 PM
tony
its no fun bit like you said we dont want anyone to go boom
sanding the in side of hull was the worst
but thats over with and i sprayed the gray gel coat on the entire in side of the hull
ordered gray gel to match the original the was in the engine compartment now the complete inside of the hull matches not that you will be able to see it once the deck is back on
but it gives me a piece of mind knowing everything is sealed for moisture
just wish i would get the foam as the tank will be delivered on monday as the shipping co. called to say it would be there by 12 noon not a fun job but the worst is over now
cant wait to get it back in the water

boatnut
09-12-2004, 05:08 PM
Dauly, Tony, thank you for the info and the guidance -- you have increased the priority of our tank change. I read somewhere that aluminum tanks should not be foamed in position because aluminum like stainless needs air/oxygen available to prevent moisture from causing surface pitting and corosion (I have seen stainless pit and corrode like this on another boat I owned). I know you guys did this correctly and I think foaming is the best support between the tank and hull so what did you do, coat the tank with something or is the compartment water tight enough (even from above) to keep corosion from happening again between the tank and the foam? Thanks Again, Ed

Tony
09-12-2004, 10:10 PM
On my aluminum tank I used a self-etching primer (DTM Dry Wash Primer) and then three coats of a 30% silicone alkyd (Steel Master 9500), both Sherwin Williams products.

On top where the foam is exposed I trimmed it flush, sealed it with two applications of resin, then painted it grey to match the hull.

I know it is kind of a controversial topic, but I cannot see how using foam, if done right, would result in any problems.