W123 300D Fuel Tank - Internal Seal/Coat or not?

[dennislarock]

I'm getting Rust @ the primary fuel filter. So, I pulled a tank from the plethora of cars that I have. I dangled a small (about 8') chain in the tank and supported it. Then, I put a couple of quarts of diesel fuel in it sloshed it around and drained... a little dirty but no rust. I then put a couple of quarts of Acetate in it sloshed it around and drained... almost 0 dirt and no rust. From what I can see (I don't have a scope) the tank looks quite clean.


So, should I Seal/Coat the inside of the tank? Or, should I just install as is? The product I see the most is Red-Kote.



What would you do? Opinions Please


Thanks


dennis