How does the inside of my gas tank look to you guys? Do I need to clean and seal it or leave it as is? Thanks, DougClick to view attachment

Welcome aboard

Has it been leaking? so far as the cleanliness, I would make sure to have a couple inline filters and change them often.

You could splash some vinegar in there and then fill it with gas. Factory never coated the steel. Just bare metal.

Never seal gas tanks, that eventually flakes off and then you’ll really be hating life. If it needs to be sealed, it needs to be replaced.

POR metal prep was what I used on mine. It’s phosphoric acid (removes the surface rust) with a zinc additive in it that helps reduce the flash rusting (yellow rust) when drying and leaves a light zinc coating that helps prevent future surface rust.

https://por15.com/a/s/products/metal-prep

To reiterate, you couldn’t pay me to use POR or anyone else’s tank sealer.

Marks suggestion of Vinegar is cheaper and will work - just a bit slower than Phosphoric acid.

Reverse electrolysis also works great but literally can take multiple days and cleanings of the electrode.

If those are just surface discolorations that tank is one of the cleanest old tanks I've seen.

Now, I second the use of Metal Ready (What Superhawk996 suggested).

If that sock is old, I'd replace it. It looks old.

Overall, your tank looks about "as good as it gets" in the "old tank competition".

I'd do a little more cleaning but what you have looks "Ready to go" in my book.

You got lucky!!!

New tanks are cheap but yours looks reusable...

Nice tank. Is that a brand new fuel filter sock? If not, put one in.

A 3rd vote for POR Metal Ready. Easy to apply and doesn't take much of the product to complete the job. Pour it in the tank and splash it around to coat all surfaces. Wait 15 minutes then rinse well with warm water.

Last year I also used it on a bumper after I stripped it completely of paint. It's been sitting bare metal for months in the open air and not a trace of rust.

I agree, I found an old fashioned shop in Tucson to "boil out" my tank (really just a very caustic fluid bath). Those guys were VERY clear. A new or cleaned out tank does not need coating, and should never be coated.

You can also use muriatic acid to dissolve rust and crud.

But be very careful if you see any rust, inside or especially on the outer surface, that the tank metal has weakened or even could leak.

Thank you for all of the good info everyone, I appreciate it.

I know I will have more questions for you guys as my 914 hasn’t been driven in 18 years!