Fuel Tank

[pelagicasd]

Nice point on the fill pressure Doug, I hadn't thought of that. A comment on the aluminum tanks though. I found some in the local dumpster years back. They had developed pin hole links and been discarded. I had a need for some aluminum plate and cut one apart. Pin hole leak on the outside but the inside was so pitted it looked like the craters on the moon! I presume it was a disimilar metal problem. Maybe from a fuel level sending unit? Walt
To: AlbinVega@yahoogroups.com
From: dougpol1@...
Date: Wed, 21 Apr 2010 15:16:05 -0400
Subject: Re: [AlbinVega] Re: Fuel Tank


I ran a machine shop a lot of years here we made all kinds of things
including fuel tanks for the Chesapeake bay Watermen and fishermen.
Very small tanks can be made from stainless but bigger ones cannot. We
made most tanks of hot rolled steel or black steel as some call it. It
does rust but lasts a long time because tanks can be made of thick
material because of it's cheapness. It does not oil can and rupture
welds. Aluminum tanks are very good for the same reason and of course
plastic tanks are the best. It used to be that tanks had to be
pressure tested to 3 lbs per square inch and I don't know what present
regulations are now, but it is easy to find out. A tank down in the
keel will oil can in most cases if the filler hose is at deck level and
filled to the top. At some point the welds in the tank will rupture
because a fill hose reaching up six foot will create 2 or 3lbs of
pressure per square inch. That is the reason for the the 3 lb test.
Remember there are thousands of square inches in the surface of a tank
and each inch will have 3lbs pushing on it so even a small tank might
have two square feet of surface on any one side. That is 288 square
inches times 3lbs to the inch for a total of 864 bounds pushing outward
on each side and doward on the bottom and upward on the top. Don't fill
your tank hose to the deck level. This is especially true if the tank
is in the keel. As a now and then thing it is ok, but as a matter of
practice it will eventually break a seam in the tank.
Doug

Douglas Pollard Albin Vega Sealegs 2225

Chris Brown wrote:

 

[dougpol1]

Yes Walt you are of course right. Electrolysis is more of a problem
with Aluminum so you have to protect it. Corrosion is less of a
problem. Like every other metal on a boat it has it's downside. I
have a good friend who makes some tanks and he swears that nothing is
any good except monel. I have also heard that monel causes desiel fuel
to gell. So Go figure??? Over the years I have been responsible for the
making of a couple hundred aluminum fuel tanks and when installed
according to directions they last 40 or 50 years. Well built steel
tanks will last 30 years. I don't know how long stainless will last as
they are illegal in the size boats we generally worked on here in the
US. I also don't know why they are illegal, but I guess the information
is out there someplace.

Douglas Pollard Albin Vega Sealegs 2225
walt/judy brown/allore wrote:

 

[SVFlyAway]

I am installing a new 13 gallon fuel tank in Flyaway. Thus, I have an old
fuel tank, filler hose, and filler deck fitting. I want to get rid of this
tank.

It is Stainless.
I is built to fit against the forward bulkhead on the port side cockpit
locker. It is from a series two Vega.
To my knowledge it doesn't leak (but it might be prudent to have it
inspected I guess).
It has an eight inch clean out port on the top of the tank (that alone is
worth $40+ bucks). The tank probably needs cleaning as it has been sitting
for awhile, but that is easy with this big port.
I live in the greater Seattle Washington area. I don't think it would be
easy, or worth, shipping. I guess it could be shipped if it was steam
cleaned, but the overall cost would make it pretty steep.

Finally, all of this is free (and as is) to the first taker on email or
phone. If you live in the general area we can arrange a place and time for
pick-up (my boat is actually in Everett, but I have the tank at my condo in
Lynnwood).

Chris

206.854.6857