Where is the surface rust? If at the bottom then on the one hand it will
have petrol covering it so shouldn't rust further, but on the other when
condensation slowly develops in the tank it *will* have water on the bottom.
However it needs both water and air to rust, so should still be OK. If
higher up i.e. above the fuel line a significant amount of the time then it
could continue to rust. One hears of internal coatings one can pour in and
swill round, but one also hears that they block the screen and suction pipe
where these are part of the tanks construction. Why bother with a drain
plug? the tank should be fit and forget item once externally painted. You
can change senders (which should be another infrequent exercise) with up to
1/4 tank if you raise the right rear corner. However if it *is* a Heritage
tank, I'd expect them to be 'correct' i.e. have a drain plug if one was
provided on that model originally. What year is the car? I thought only
the early strap-on tanks had a drain plug, and Heritage don't seem to do
----- Original Message -----
> ... I plan to clean with Simple Green,
> then etch and seal using the Moss products.
> Secondly, I would like to add a drain plug.