Gas Tank Rust

[Dale Traylor]

I removed the gas tank from my 1969. I found the tank sticker, but some rust also. The rust is surface rust, my question is "what is the recomended way to treat it before I put it back in the car?" Keeping in mind that my goal is to enter the car for judging as an unrestored original at THE NCRS meet in Orlando in January.

[Jerry Clark]

Re: Gas Tank Rust

you really only have two choices.....one actually;
you can have it redipped, relatively expensive.
two, replace it with one from Quanta.
jer

[John H.]

Re: Gas Tank Rust

Dale -

If you intend to present it as a Bowtie candidate, don't touch it - just leave it alone, or it could cost you big time if you get to Bowtie judging/voting. If you don't have it already, you need to get a copy of the white-cover "Corvette Judging Reference Manual" from the NCRS Store on this site, and read the section thoroughly on the Bowtie Award; it gives solid advice on what NOT to do in preparing a Bowtie candidate for judging. There is NO consideration in Bowtie judging for "Condition" - only absolute Originality.

[Joe L.]

Re: Gas Tank Rust

Dale-----

It depends where the rust is located. If it's on the top of the tank, simply remove with a BRASS wire wheel and paint the area with a cold galvanizing compound or gas tank finish restoration paint available from Eastwood. No one will ever see this area with the tank installed in the car. Even the bottom of the tank is virtually impossible to see when installed in the car, The lower corners and tank sides may be visible if someone really tries.

Otherwise, do as Jerry says; you can get an exact reproduction tank from Quanta products.

[Jerry Clark]

Re: Gas Tank Rust

Good point...I continue to fail to take Bow Tie into consideration
jer the hot rodder

[Jack H.]

In Star/Bowtie judging....

condition has NO MEANING. Only originality counts. So, the fact that there's minor rust on the gas tank has absolutely no impact on the car's judging outcome....

But, I guess I don't understand how you expect to have the car Star/Bowtie 'judged' in Florida next winter.... Unrestored cars are only judged at the NCRS National Convention (a once a year event) which will be in Windsor, Ontario next summer.

Maybe you mean you intend to 'present' the car as a Bowtie candidate in Florida next winter. If that's the case, inspection will be brief and rather cursory (is this a legitimate Star/Bowtie contender? -- if so, you get a ticket to 'ride' good for the upcoming National in Windsor). BTW, doing things like dropping a gas tank 'can' hurt you in pursuit of unrestored Corvette awards. Evidence that this/that has been changed/altered can count against the car, so that's why others have suggested you DO NOTHING to 'prepare' the car for judging.

[Patrick H.]

Re: In Star/Bowtie judging....

jack,

Two additions/changes to your comments:

1. Evaluation for Bowtie has changed as of April 1. It is no longer cursory, but consists of a full evaluation just like Flight Judging. In fact, you essentially get judged on the Originality section ONLY of the Flight judging sheets. They prefer that you just have it Flight Judged, and go through the whole thing. They charge you the same $ as FJ, so why not? My 72 received this evaluation at Seven Springs (I had it FJ'ed) and is a candidate for Windsor's Bowtie Judging.

2. Condition "does" count, as a bad original paint job or corroded original chassis or shredded original interior will lead the judges to agree that the car is original but have them vote that it is NOT worthy of using as a Star/Bowtie car in the area being judged. You can then NOT receive a Star, essentialy due to condition. You and I have both seen this happen.

But, if you're considering Star/Bowtie judging, then don't touch the gas tank. Mine has light rust, too, but it stays put for now.

Patrick

[Tracy C.]

Re: Gas Tank Rust

Dale,

You've recieved some excellent advice from those who have been there. I haven't.....But you’ve gone to the trouble to pull everything apart, so I understand why you wouldn’t want to put a rusty part back in your car.

Here’s a tip that works great for many applications…..but please be carefull!!

Mild surface rust can be easily removed with muratic acid, but you really need to be careful and follow ALL 10 of these steps. (Muratic acid is available at most hardware stores for about $4 gallon.)

1) Remove the tank from the frame and take it to an outside location with PLENTY of ventilation.

2) Get a 5 gal bucket of warm water and dissolve a box of Arm & Hammer baking soda in it. Throw in a car wash mitt and keep it handy.

3) Buy a pair of elbow length rubber gloves and some 00 steel wool

4) Pour a pint of muratic acid in a smaller bucket.

5) Take a cheap paint brush and brush the acid over the surface rust and work the area with the steel wool

6) Repeat step 5 until the rust is gone.

7) Wash the entire tank over good with the baking soda water and the car wash mitt from the 5 gallon bucket. (the soda water will neutralize the acid…very important!!)

8 Repeat step 7 and rinse with fresh water from a garden hose.

9) Dry the tank immediately and apply a very liberal coating of WD-40 to the entire tank’s surface.

10) Piddle dink around between steps 8 and 9, and you get to start with step 5 again.

Caution…..

DO NOT breathe the vapors off the acid. And wash any acid off your skin with the baking soda water ASAP.

Dispose of the remaining acid properly, you will stay on good terms with Big Brother these way. I usually just pour it back into the jug for next time.

Good Luck
tc

[Kevin Whiteley]

Re: Gas Tank Rust

For a more mild solution of muriatic acid, just add water (w/o soda). The acid solution works just as well, and is alot safer. I believe most bottles of acid will indicate the best proportion for solution. Note: pour acid to water, NOT water to acid.

I used the muriatic solution on my smoke stained fireplace, which was alot more difficult to clean than any vehicle part I've ever come across, and the bricks cleaned up very nicely. (Slightly off topic, but safety first)

With the solution, you can simply pour the remainder on a driveway, brick walk, etc, and clean with a stiff bristled brush (it's legal in TX). Not only will you get a clean gas tank, but a clean driveway also.

[Chuck S.]

Re: Gas Tank Rust

I agree with Tracy that if the tank is to be restored, muriatic acid is the best way to clean off the rust. Mechanical cleaning will not remove the rust completely, and it will tend to return under most protective finishes.

Tracy has some good detailed information and covered the bases. Kevin is also correct; a dilute solution is the way to go. Note that the galvanizing on the gas tank is probably only a few thousandths thick, and I wouldn't take off any more galvanizing than I needed. Unless you are going to store the solution (more on this in a minute), I would probably only mix maybe a quart or less of solution using one to two onces of acid per cup of water. You can always mix more or mix it stronger if needed. WEAR EYE PROTECTION!

Now, about muriatic acid storage to the uninitiated: Take extra care to insure that storage containers are not damaged or spilled in your crowded, cluttered restoration garage. If you have a spill and you are somehow unaware or ignore it ("Don't worry", he said, "it's contained on that plastic storage container lid!"), the vapors off muriatic acid solution will cause EVERYTHING in your garage to RUST more than it normally would in decades. It will ruin every ferrous part on your restoration, and recovery from this disaster will consume many manhours. Muriatic acid can be a great help with rust removal, but you better give it respect, or you'll pay.

Also, Kevin, I am not sure I would pour the leftover solution on my driveway unless the driveway is very dirty (note that muriatic acid won't touch collected oil drips) or you like a rough appearance. The amount of etching will depend on the strength of the solution and the time of exposure, but muriatic acid eats concrete with gusto. Muriatic acid is typically used for etching garage floors prior to sealing or painting; the roughness improves adhesion.