T&T: Black Iron Fuel Tank Leaking

[Faure, Marin]

>If any of you have experience sealing a diesel tank from the inside
using one of the products or types of products mentioned above I would
surely appreciate learning from your success or failures.


I've repaired a leaking weld seam in a steel fuel tank in a vehicle
(1973 Land Rover) with aircraft sloshing compound.  Here's the challenge
you face--- assuming all these sloshing compounds work the same, they
call them "sloshing" for a reason.  You have to have the tank fully out
of the vehicle, boat, plane, etc. for them to work.  What you do is
first clean out the tanks thoroughly.  I seem to recall that you even
have to remove rust from the inside of the tank by turning it over and
over with a bunch of nuts and bolts or something inside it to break up
any scale that might have formed and then thoroughly clean out this
stuff, too, but I could be misremembering this part.

But in any event, to apply the sloshing compound you pour it into the
tank, seal up all the holes in the tank (filler hole, breather, fuel
feed hole, etc.) and then turn the tank every which way including upside
down to thoroughly slosh (distribute) the compound over the entire
inside surface.  You do this for a specified amount of time (30 minutes
maybe? I don't remember) while the sloshing compound firms up so it
won't run off the vertical inside surfaces when you stop "sloshing" the
tank.  Then it has to sit for x-number of hours/days for the coating to
cure.  Then you can put the tank back in the vehicle/boat/plane.

The compound worked for awhile to seal up the leaks in my Land Rover
fuel tank but the leak soon came back although not because the coating
itself failed.  So I ended up installing a brand new tank.  But based on
my experience I think it's a valid repair method, at least for a time.
I don't know how long this sort of a repair will last, however. And I
was using it on a gasoline fuel tank, not a diesel tank, so I don't know
if the aircraft sloshing compound I used was approved for use with
diesel fuel.


______________________________
C. Marin Faure
GB36-403 "La Perouse"
Bellingham, Washington