That old topic...I am replacing my Tank

Hooper · #1 12-23-2004, 06:10 PM

Hello Guys-

I am soon to begin the one winter project I need to complete on my '83 23' CC, put a new tank in before next season. I am still on the original tank, so I figure that I better do it now, rather than have it go on me in June...

I have never done anything like this before, but I don't expect it can be as hard as building the pyramids, I hope.

So, before I begin, what advise can you offer me on this project??? I have read all the archived material I can find on the subject, but still know little on what I will have to do.

First I'll need to unwire anything that prevents me from moving the console, then remove the console to have access to the deck, open up the deck and gain access to the tank.

I believe the tank is foamed in, so I will have to remove that somehow... someone on here used a chainsaw, but I am sure there are other ways too.

Remove the tank and bring it to a fabricator.

Once out, I figure I will need to inspect stringers and any other potential probelm areas which I may see with the tank out.

Once built, I'll need to replace the tank and foam it back in place, right???? How the hell does that work and what should I use????

I could really use a few words to point me in the right direction. I figure I will start removing some wiring soon so that I can move the console for access....

Thanks for anyone who might be able to get me started!!!! [img]/images/graemlins/smile.gif[/img]

RS · #2 12-23-2004, 06:27 PM

You might want to read this article:

How to Install an Aluminum Fuel Tank

warthog5 · #3 12-23-2004, 06:28 PM

QUOTE: I believe the tank is foamed in, so I will have to remove that somehow... someone on here used a chainsaw, but I am sure there are other ways too.

I recommend that you use a blade from a Bow saw.[tree trimming saw] Use just the blade. It's about 18in long. Wrap one end with cardboard and duct tape. It's long enough to go to the bottom of the hull and is VERY agressive so it will cut fast.

QUOTE: Once built, I'll need to replace the tank and foam it back in place, right???? How the hell does that work and what should I use????

Clean the alum well and sand the tank with 60gt on a DA sander. Then roll on 2 coats of Coal Tar epoxy. I rolled a thin coat of regular epoxy on top of that on mine. Use 4lb density foam to refoam it in. You can get 4lb density from FGCI.com

warthog5 · #4 12-23-2004, 06:33 PM

The artical by Dave Pascoe is good, but it has falts in it too. His whole deal stems around getting air moving thru your bildge. On big boats that is possible. On these SeaCrafts it's not. He talks about water getting traped in the foam and working on the alum. So don't let water get in there and protect the alum if it does.

Finster · #5 12-23-2004, 06:59 PM

Quote:

air moving thru your bildge. On big boats that is possible. On these SeaCrafts it's not.

Your loosing me. [img]/images/graemlins/confused.gif[/img] The 23's have vents on both sides fore and aft just for the purpose of hull/bildge ventilation.

RS · #6 12-23-2004, 07:38 PM

Quote:

His whole deal stems around getting air moving thru your bildge.

That's not how I read it. The whole deal stems from not ever letting water stay in contact with the aluminum for long periods, as in wet foam against the tank. Space for air is needed, not necessarily active air circulation.

Also, I'd be concerned about using coal tar if he is corect about carbon being cathodic to aluminum and causing galvanic corrosion.

Hooper · #7 12-23-2004, 08:12 PM

Quote:

Use 4lb density foam to refoam it in. You can get 4lb density from FGCI.com

How much of this stuff do you think I'd need??? Again, you're dealing with a clueless person!!! [img]/images/graemlins/laugh.gif[/img]

Also, am I correct in thinking that this foam stuff is the only thing holding the new tank in place? No straps or anything? I am sure I'll see things more clearly once I open her up, but I just don't know how it all comes together.

Scott · #8 12-23-2004, 08:53 PM

Hey Hopper ...How ya been ??

Can speak for all ... but my tank had tabs welded right on it that were used to anchor it into the stringers …and that dreaded foam

Don’t know about the "newer" boats but most of the older ones had vents forward and aft (unless closed in during a restore) Those vents allow air flow into and throughout the bilge ...Edit ...I see thats what Finny already said

Hooper · #9 12-23-2004, 08:59 PM

Hi Scott-

I'm doing fine, thanks! Got time now to read my favorite sites and do some boat fixin' if it doesn't get too damn cold!!!

Ok, so the tank has welded "feet" (for lack of the proper term) which are then fastened to the stringers I would assume, is that right? I would guess as long as I don't have any rot going on at that point I can refasten with the new tank.... hmmmm.

I appreciate the help guys, I am also sizing up this project and deciding if it is too much for my limited experience!

-Hooper

Scott · #10 12-23-2004, 09:17 PM

Good to see ya around !!!

Actually those tabs are up at the top of the tank ... When you get under the deck yours may be different

They had a 90 degree piece of aluminum along either side ...so you could fasten it as much as you wanted ...If you had room, tabs on the bottom might not be a bad idea

Wet foam killed my tank ...only down on the bottom 2-3" of the sides ...It held the water and corroded the tank (no coating). The three builders I have talked to (in NJ) either include or offer epoxy coating.