1987 Aquasport 170 - fuel tank installation question

[wwwcre8r]

Recently bought this boat, previous owner said he smelled gas, pumped out tank and switched to a 6 gal portable.

I have the console off, the coffin lid up... found a badly corroded 29 gal aluminum tank in her. Had hundreds of 1/16" to 1/8" holes, only in the top though.

Went to Alloy Metal Works Inc., in Farmingdale, NY this morning, met with Phil, he's going to build me a new tank (in about a week).

QUESTION: I've read that I should adhere fibre reinforced plastic strips on the bottom with 3M 5200 adhesive --- where can I get such strips? What might be a suitable substitute? If I use the method described here: http://www.yachtsurvey.com/fueltank.htm --- should I use the stainless steel straps that are in there now to hold the tank down? I don't want to if I don't have to... the less touching/ rubbing against the tank, the better IMHO.

What do you think (thanks in advance)?

[aiezzi]

pics please

[John Jones]

Those Haysite brand strips he mentioned are about $7/foot in 1 in. width.  I would go to a NAPA auto parts and find some kind of 1/4" thick waterproof gasket material.

from Yacht Survey. The 5200 is so strong and will create so much suction that you not need any other method of securement.

You can find the reinforced plastic sheets or strips at www.macmaster.com.

[wwwcre8r]

Thanks for the info, I'll post picts after the holiday.

Guess I'm not going to buy the Haysite strips -> too much $

That link didn't work, sent me to:
"The MacMaster House Bed & Breakfast Inn"

[John Jones]

Ooops.  It shouldn't have had the 'a' in it.

http://www.mcmaster.com/

[wwwcre8r]

Thanks again for the help!  

I guess this should work:
6', 3" Rectangular Strip 3345K21 $8.74

I trust this material should hold up to a marine environment/ being in a fuel tank coffin.

[John Jones]

If that is what I think it is, it is as hard as concrete.  They say it is in the "phenolic" family.  That is used in electrial switch gear.  It is very durable but there will be no cushioning from it.  It also says use indoors.

[Bushleaguer]

cre8r-
I am getting ready to do the same on my 1987 222 Osprey.  When you lift the console up to access the fuel tank hatch, did you just loosen the screws and lift it up a bit, or did you completely remove the console?  I'm debating on whether to remove and re-wire the console while I'm at it.

Also, to remove the fuel hatch, what's involved?  It looks like I have some 5200 to remove (utility knife work??) around the edge, as well as the hatch screws.  Did you have a hard time getting the hatch loose?

I don't have any leaks that I know of, or any odor of gas, but just figure that after 20 years it would be good to have a look and replace hoses.  Also have a bad sender and need to replace as well.

Appreciate any advice!!

[GoneFission]

As an example, you could look at what I did when replacing my tank:

http://www.classicaquasport.com/forum/v ... php?t=2597

Good luck!

[Bushleaguer]

Thanks Fission!  I actually found your pics and studied them before I started.  I have been working at it for a few days and it's going fairly well.  I got the tank out in a good 8 hour day.  Lots and lots of utility knife work.  When I got the hatch off, the basin and tank were completely covered in wet black slime.  I did lots of scrubbing, scraping and washing and got everything pretty well cleaned up.  The tank is in pretty good shape, except for a few pits in the area where the tie down straps were.  Bottom corners were the worst, but really not that bad.

I've been thinking about what to do next.  Since the tank wasn't leaking to begin with, I don't think I need a new tank.  It is in pretty good shape except for the pitting.  There are three areas on the bottom corners with about 3 or 4 pits each and they really aren't too deep.  The guage of the metal on the tank is .125 according to the tag, and I would say the pits are not even 1/3 that deep.

On the other hand, I would hate to go to all the trouble of an install and have the pitted spots leak in a couple of years.  I have considered these options:

1) Try to braise up the pits with one of the advertized alluminum rods like alumaweld or HTS-2000.  I'm confident that I could do the repairs, but am deathly afraid of having the tank blow up.  The application requires heating the metal up to 750 degrees with an open flame torch, and I've read that you can never get all the fumes out of a gas tank.

2) Coat the tank with Gluv-it.  This is a two part epoxy coating made by Marine Tex that is made for coating aluminum.  It claims to be made to penetrate, seal and stop corrosion.  

3)  Buy a new tank.  (I'd have to really be forced into this option).

It was obvious that the places that trap water against the tank (hold down straps) were the problem spots.  When re-installing, I'm thinking of following the install described by Pascoe on docksidereports.com.  

Since this tank has lasted 20 years, I think one of the two options listed will get me another 20.

Any thoughts?  Has anyone had any experience welding or braising an aluminum gas tank and lived to tell about it?

I do have pics, but have no idea how to post them.  I'm working on that.

[Bushleaguer]

Taking a crack at posting pics.  There should be three:

[wwwcre8r]

cre8r-
I am getting ready to do the same on my 1987 222 Osprey.  When you lift the console up to access the fuel tank hatch, did you just loosen the screws and lift it up a bit, or did you completely remove the console?  I'm debating on whether to remove and re-wire the console while I'm at it.

Also, to remove the fuel hatch, what's involved?  It looks like I have some 5200 to remove (utility knife work??) around the edge, as well as the hatch screws.  Did you have a hard time getting the hatch loose?

I don't have any leaks that I know of, or any odor of gas, but just figure that after 20 years it would be good to have a look and replace hoses.  Also have a bad sender and need to replace as well.

Appreciate any advice!!

Sorry it took so long to get back to you... I pulled up and tilted back the console (mine has a hard-top bimini), quite heavy. I bought the new tank from Phil R., bought a sheet of Starboard, cut it into strips and applied with 5200.

While doing this I noticed the wiring was old and nasty, really done poorly; wirenuts, electrical tape peeling off splices, wires severly nicked and left that way... only one gauge worked, etc. So I am labeling / ripping out all wiring and redoing it proper --- only thing is I'm not an electrician, so doing the best I can, I created a new wiring diagram in Visio to help.

My new digital camera comes on Tues., I'll try to get some picts up shortly thereafter.

[wwwcre8r]

Pictures *finally* posted  :)
I attached them up top to my original post.

[Bushleaguer]

cre8or-
Glad you are making progress.  Here is where I ended up:

I thouroughly cleaned the tank with brush and soap.  Then wiped down with laquer thinner.  Then etched with the following:
 
 

Then, I dried off the tank and glued FRP strips on the bottom with 5200.  I ran the plastic strip starboard to port, rather than fore to aft.  This enabled me to place the strips under the tank baffles for more support.  I left room for water to drain down the middle and around the edges if necessary.  My tank has an angled bottom, matching the deadrise angle of the hull for more capacity.



Then, I coated the tank with two coats of Glu-Vit epoxy by marine tex.  It seemed to do a great job penetrating the few pits I had in the tank.  I am very confident that the tank will last for another 20 years.







After the epoxy cured, I ran 5200 along the bottom of the FRP strips, dropped the tank into the coffin box and connected the new hoses.  I then filled the tank up 3/4 to check for leaks and to get some weight on that 5200 to bond the tank in place.  New sender, wires and clamps and I put the lid back on.  I didn't use any hold down straps of any kind.  I'm confident that that tank won't go anywhere- that 5200 is pretty strong stuff.

It was a ton of work, but I now can go out and not worry about what is going on in that fuel hatch :!:

[wwwcre8r]

Then, I coated the tank with two coats of Glu-Vit epoxy by marine tex.  It seemed to do a great job penetrating the few pits I had in the tank.  I am very confident that the tank will last for another 20 years.

Ooo, now you got me thinking... on a new tank such as mine, would there be much advantage in coating my tank in Gluvit? I tend to lean towards overkill regarding details in my work... if it might make the tank last any longer... I might just do it.  :)