Gas Tank where to start

Going to start restoring my gas tank from the 64, I know the first thing I should do is see if it leak by my guessing filling up with water and letting it set a few days. (can't do that just yet or I've a 16 gal ice cube) Will do this in the end of Feb.

My question is if it don't leak what do I clean it out with??? This tank I bet hasn't had new gas in 8 years and sure theres sludge in there. Also what takes off undercoat good??? This stuff comes off hard and don't want to get too agressive and put a hole in it myself. I would like to clean it good to paint it. I already plan to have the sender rebuilt

I used a hot air gun and a good scraper to get alot of the undercoating off. alsos it seemed like if you heat it up and then let it sit for a couple minutes some of it came of in bigger chunks for some reason. then I used alot of scotchbrite pads on a die grinder.

Chris,
Depending on if your in a rush or not you can use "Under Gone Undercoating Remover". You can get it from Eastwood, about $12 a can, one will do it. Or if you have time poor some straight anti-freeze in it and shake it around, then poor some all over the outside. It will cause the sludge on the inside and undercoating to break down. It takes about a week for the undercoating and only a few hours for the sludge depending on how bad your is..

And yes, the anti-freeze takes a little extra time but..... No cost and very little effort!

Still on the subject of gas tanks ,, I learned something today,, make sure you have your bumper brackets in "Before" you install the tank.

all great information here.....
Bill how should I check it for leaks????
Digz I'll b good no bumpers on this van, but great infor for others
Dan I only hope my tank looks even half as good as your. (looks new) I'm going to try the anti-freeze first. Did you put it in a kiddie pool to soak it????
Don I will look into the hot tanking if this doesn't get all the crap out if it leaks may have to have them repair it anyway.
64chevy I have also heard of the pee stone & acid trick , you guy have given me alot of ways to go. Thank You

Only on one side Joe Been there done that

Thanks Bill I'll wait for warmer weather to fill it with gas, going to clean everything first and be careful doing it. I know the cleaning alone could cause a leak that would have happened down the road. The infor on the sealer is great because I was looking at it somewhere and it was white

Don as you can see I haven't pull the sending and I remember that picture from a while ago and hope mine isn't that bad.

I tried the stud welder on a dent in 1 of my tanks. Now I got a hole & a dent

I brought my tank to a good radiator shop and they cooked the crud out of it and, as Joe said, that leaves the inside susceptible to rust. So then they applied the inner coating, which is beer colored. Feels like smooth plastic. And they can pressure test it for leaks. It wasn't cheap though. I think it cost $150 or more.

Lesson to you all: when you get your new van home, drain the tank first thing! Mine might have been much better if I hadn't let it sit for a YEAR before I drained it!

I think those welded studs might have worked to pull the dent out if you could pull on all of them at once. But how do you do that?

wow that earlier pic is incredibly cruddy. Will have to drop mine to see. Has a big old dent in the bottom from prior owner backing over something. Was going to remove it and burp (carefully) some compressed air into it to fill it out. Am not worried about scrapes and dings as long as it can hold close to spec fuel. Might put a reserve tank somewhere else above it that I can open a valve and let it flow into the original tank (hey I'm an old VW guy and that saved having a fuel guage from about 1939 to 1963--just fill up whenever you go to reserve).

Has anybody tried that POR-15 tank kit? It includes a pre-wash, acid and tank coating. Would love to know if it is holding up, over the years, for anybody.

Thanks much and happy motoring, Mark

my merc had a couple holes in the tank when i got her so i put screws in the holes with jb weld on them and then covered them with more jb, lasted for 3 years until i could put in a new tank. not the right way to do it but thats what i had to do.
jeff

Opened the tank today and happy with what I saw looks good in there and should clean up well. even the sender look in good shape, screen is clean and everything moves freely. I do have a pretty good dent in the bottom that I would like to pull out.

After taking Don's advice I dropped the tank and glad I did. Although this van was used as a daily driver 44 years took it's toll. The outside is in good shape with no dents or rust. Found stuff in the tank that I don't know if it's part of the fill tube or a midnight theft gone bad. Thinking of sending the gauge to be repaired in Ohio or NY. Don't know of any on the west coast. Does the antifreeze for the inside really work without damaging the coating? There's a thin layer of gunk on the bottom and haven't found the screen yet.