68 corvette gas tank questions, L@@K!

[Terry F.]

Ok, here goes. Maybe the 68 corvette people will know this stuff, anyone else can respond also.

1) What direction does the O.L. Anderson logo point on the bottom of the gas tank?

2) Where is the logo located on your tank (ie. between the tank sending unit and the back side of the tank). Should be able to feel it by reaching up in there.

3) Can you tell if your tank is zinc plated or plain sheet metal?

4) Does your gas cap have a SMC stamp on the underside and does it have a rubber or fiber gasket to seal it on the tank flange.

5) If your tank has never been out or you took it out personally...Did your tank straps have any padding between them and the tank? I believe the AIM does not show any there but I have found it on atleast 2 cars.

Thanks in advance, Terry

[mike cobine]

Re: 68 corvette gas tank questions, L@@K!

My tank is sitting in a storage area right now, so I'll have to check this weekend. However, it did have a tarpaper-like padding on several sections. I'll have to look to see exactly where it was at.

[Kurt B.]

Re: 68 corvette gas tank questions, L@@K!

Have owned my 68 since 1972
#4 My gas cap has no SMC stamp or any kind of stamp on it. Also, no rubber gasket and judging from how tight my cap fits, I think it would not fit if it did have a gasket.
#5 My gas tank straps have padding and I have never removed it and doubt the original owner did in the first 4 years he owned it prior to my purchase.
Kurt # 26406

[Rich G.]

Re: 68 corvette gas tank questions, L@@K!

Hi Terry

The logo is half way between the sender and the back of the tank. The top of the "A" points to the right when holding the tank so that the front is up. Or if the tank was installed, the top of the "A" points to the right side of the car.

This tank has remains of the padding material that feels like thick tar paper.

The tank does not appear rust proofed. It has rusted thru in spots.

I don't have the cap here, but I'll look tomorrow. I know it DOES NOT have a rubber gasket. I think it has only a paper-like thin gasket. I recall it was correct per the TM&JG, for what that's worth.

Rich

[Terry M.]

Re: 68 corvette gas tank questions, L@@K!

3) I have seen an inkstamp on the metal that the gas tanks are made from -- ARMCO -- same company that makes many of the metal roadside barriers. The parent material is, I believe, galvanized sheet stock. That is to say it is electroplated before the tank is formed. Galvanizing is a form of zinc plating. I can't tell you that the tank I saw with the ARMCO label on it was from a 1968, but I doubt the 1968 tanks were made from a different material than other year gas tanks.

[Jim T.]

Re: 68 corvette gas tank questions, L@@K!

Information from 68 original owner convertible. The gas cap does have the SM circled by a big C and then a circle line around that. This is on the underside of the cap. Hope yours is vented, all 68's were. The gasket is now rubber like what is used on the parts counter available locking gas cap. The gasket is very durable, the 68's is less in width than my 70's gasket. Check the archives for Joe Lucia, some time back there were some postings of what this gasket is made of. The previous poster Terry also had some input on the gas cap posting. My tank is not plain sheet metal, and it does have some surface rust. I should remove it and clean it up and spray it, probably will when I have more time to take care of it. The original padding is still in place and in good condition from what I can see that the gas tank sits on. and I just looked at it since the car is on one of my lifts. It resembles a heavy or thick tar paper cut in strips. It is more difficult to see anything under the two retaining straps, I did feel around both staps and there is a thinner padding between the tank and strap contact area. It is a fiber type product. Did notice some cracking in the supply gas line hose, have replaced it once and will now do it again.

[Terry F.]

Re: 68 corvette gas tank questions, L@@K!

I bet if you take a magnifying glass and look mid way around the underside of the gas cap you will find a very faintly stamp SMC. It is round and the "SM" are inside the "C". I looked at mine and thought for sure it was not there. But in good sunlight it is there. I laughed when I found it. I must be crazy looking for this stuff. Mine has the rubber gasket but it is trashed. Thank you for taking the time to respond. Regards, Terry

[Terry F.]

Major thanks for responding! Terry *NM*

[Terry F.]

Re: 68 corvette gas tank questions, L@@K!

It's really hard to tell about the zinc coating because I think it wares off. As I recall from a chemistry class years ago, it is sacrificed and slowly wares off in an electrochemical reaction. Once, it is worn off the tank starts to rust. Probably looked good for a few years. Thanks for responding, Terry

[Kurt B.]

Re: 68 corvette gas tank questions, L@@K!

You are correct and I was wrong. I just looked with a magnifying glass and there was the SMC logo just like you said. I was looking in the wrong place on the cap and also without the magnifying glass it is barely legible. I learned something today. Thank you.
Kurt

[Terry F.]

Re: 68 corvette gas tank questions, L@@K!

Interesting...thanks a bunch! I wonder what the padding under the straps is. It seems different than the asphalt strips that are under the tank supports. Hmmmm. I have seen it around though. It may be the same stuff but just thinner strips. If anyone knows I hope they comment.

So...it looks as though it is possible the cap could have either a fiber or rubber gasket, should have the SMC logo. The judging manual says it should be fiber. There may have been a transition in that year.

Tank supports have the asphalt paper type strips under them and the straps have some sort of fiber paper padding on them that is not asphault coated. I will look at what's left of mine tomorrow. It has a cross pattern that reminds me of canvas type strapping.

The OL Anderson logo belongs between the sending unit and the front of the tank and points to the right side of the tank (passenger side).

I wonder how reproduction tanks from Quanta compare to this?

Thanks a bunch! Maybe we will get some more posts. Terry

[Terry F.]

Re: 68 corvette gas tank questions, L@@K!

On some they are easy to see. Mine is so faint but it is there. Almost like saying what's the point if you are going to make it so hard to see. I don't think 68 tanks were dated. Terry

[Terry F.]

Re: 68 corvette gas tank questions, L@@K!

Jim, does your tank have a date on the outer ring that surrounds the tank sending unit? Thanks, Terry

[John H.]

Re: 68 corvette gas tank questions, L@@K!

The tank material is "terne-plate"; similar to electro-galvanized, but it has a very high lead content in addition to the zinc galvanize. It was terne-plated as coil stock prior to stamping and welding.

[Terry F.]

Thanks, Terry. *NM*