On 8/3/2010 8:43 PM, Bruce in alaska wrote:
In ,
wrote:

My steel diesel tank has developed a small hole due to rust. I can't
take it out of the boat without removing the engine. Aside from this
pin hole the tanks looks in good shape. Have any of you used some sort
of coating on the inside of diesel tank to plug the leaking hole and
prevent further leaks?
Thanks for your recommendations.

It really depends on just WHERE in tank the pinhole is located. If it
was Sandpit caused, and somewhere up on the side of the tank, then just
use the fuel to a point that is lower than the leak, and then Dill& Tap
the pinhole, with a 1/4 inch fine thread Tap and screw a bolt and O-Ring
into the Drilled& Tapped hole. You could also just pump the tank out,
and then do that kind of repair, on the tank, as well. If the tank is
OLD, and had lots of water in it, over the years, you may want to get it
tested with a Ultrasonic Thickness Gauge, and see just how much metal is
left, in the tank walls. that is how the BIG Boys do it. Been there,
done that....

Thank you all for your comments and suggestions.
To clarify the situation the pin hole is at the lowest point of the
tank, where water would indeed collect.
I think I am going to empty it and install a drain, as suggested, where
the hole is.
Doing a search on the net I saw an epoxy GasPruf 130
(http://www.thinfilmtech.net/products...PRUF%20130.pdf)
that is purposely used where water or fuel is present which is cool.
There are other compounds available for sealing the interior of fuel
tanks but the tank has to be totally cleaned before the application.
http://www.flamemaster.com/TechnicalsPDF/cs3204.pdf
http://www.microleak.com/brochnew.htm

Here is a forum where I got the information:
http://www.activeboard.com/forum.spa...picID=22121815

Boeland