So I just dropped my gas tank out of my 88 GTU. There is a LOT of sediment and rust-looking stuff. I don't think the interior of the tank itself is rusted out, so it should be good. Does anyone know how I can clean all this crap out though?

If I can't clean it, I might just buy a fuel cell, or maybe just buy a new tank. But I'd like to explore the free option first.

 

Theres all kinds of ways to do that. The hole for the fuel pump should be big enough for your hand and arm. . . You can use something abrasive like scotchbrite pads, or chemical (anti rust chemical like naval jelly, etc. ) Physical labor would be required on all forms. . . scrubbing etc.

Once you've cleaned the residual you will be able to asses the condition of the tank, and then decide whether or not to replace.

 

I was thinking about dumping in a few cans of seafoam in there... Think that might help a bit?

 

There are places that you can send your gas tank out to I believe they boil the tank as part of the cleaning process. I forgot what they told me over the phone but I remember they mentioned boiling.

New gas tanks are discontinued from Mazda! I know, I tried getting one about a month ago. Had mine professionally cleaned instead

 

Who did you send it to? I'm going to be doing this as well later this year.

 

Many radiator shops can also "boil out" a gas tank.
Often, this is followed with a resealing treatment of some sort.

I've seen treatments that involve some sort of chemical etch combined with mechanical debradement (basically, drop in a few pounds of ball bearings and shake to remove loose deposits).

Since it's still relatively simple to find good condition tanks in junkyards that's where I'd start if your current tank is in bad condition.