tnovot

I would like to find out if the gas tank bladder material is rubber, neoprene, or some other material. Now that I can no longer find gas without alcohol, I am concerned that the ethanol could attack and deteriorate the bladder. If it is detrimental, I can get 110 octane unleaded racing fuel and/or 100 octane aviation gas but both are leaded and will cost me about double the price per gallon.
Would another option be just to remove the bladder and use available gasohol?
Terry

Durango_Boy

I don't know if you have a bladder or not. You might have a plastic shell inside yours being the year and all. Mine had a rubber bladder and I removed mine. I ended up with a bit extra capacity too.

If yours has the shell it'll be very hard to get out I think. If it's rubber...go for it.

Solid LT1

Tank was lined with fuel cell bladder Fuel Safe in Oregon has replacemnt liner avalible. Not cheap but if someone hammered into your Vette, it would probably make life better.

turtlevette

I'm starting to wonder what planet some of you are living on. I've been using 10% ethanol in my car since 1980 in Louisiana, Colorado and Mass. I thought it was everywhere. I've not seen it deteriorate the rubber bladder, or lines. Oil company BS.

mdbelanger

My 77 has the rubber or what ever material its made of. So far there isn't a problem. Pulled mine and checked the condition to see if it had collapsed. Not a problem. I would watch the rubber line before the fuel pump before worrying about the tank. If your bladder has collasped there is the possibility of two problems: #1 rust hole in tank. #2 there is a vac line to the charcoal for fumes. On top of the tank that vac line goes to both sides of the liner. You will see the "T" fitting to keep a balance of neg. pressure. From what I have learned the bladder is to protect you from a rear end collision. Possibly the steel tank could rupture and the bladder is there to help you from burning to death.

What the hell are you doing by giving advise to override a safty feature without giving a warning just to gain a pint of gas.??????????

I think most of us folks do override a safty feature, yet when giving advice to do so I believe you should give a warning unless you wish to cause bodliy harm.

My honest thoughts.

Michael.

tnovot

Mine is a 1975 - just looks like a 80-81 because of the front end.

Didn't intend to start a mean spirited controversy. Still don't know what material the blader is made of. Maybe someone can still answer my question without getting hostile to the other respondents?
Terry

mdbelanger

Not being hostile. Just encouraging safty, before overriding a system without giving a warning. Also as I stated that rubber line before the fuel pump will show a problem, bloat, swell, before there is a problem with the tank liner. Cheaper rubber.

M

Durango_Boy

I know the gas tank was the same from '75 to '77 so it's very possible that your tank has the rubber bladder...I just don't know for sure.

I also have no idea if you would have deterioration problems with the fuel. I HAD to remove mine because it was torn away from the bolt flange and was getting ready to collapse into the tank. Replacing it wasn't an option so I left it out...like many other GM fuel tanks with no bladder.

That front end looks great on that car.

mdbelanger

PLEASE Show me a GM fuel tank after 1974 that is behind the rear axel that does't have a secondary safty system?

Pintos don't count.

Durango_Boy

Please. Post some data showing that if someone rear ends my Vette that I will burst into flames, and then show me data showing that I wouldn't burst into flames with the bladder in my tank.

What year did GM start putting the bladder in Corvette gas tanks?

mdbelanger

Ok hear we go. As far as I am concerned you have posted dangerous information about pulling the bladder or liner out of a fuel tank without giving a warning.

Are you so inept to think that any manufacturing company would add a safty feature that was not mandated?

I have stated that you "Drango_Boy" have given unsafe information that could cause a life threating situation.

One of us will be banned from this forum, I assume.

Or one of us will be man enough to resign.

So who is wrong before I post the INFO.

You ready to bow out?

You type enough misinformation, THIS TIME IS THE LAST FOR ONE OF US.

Michael.

Solid LT1

DA*N! I just checked Fuel Safe for pricing, I think it must be wrong, a few years back we did a new bladder for around $600 as I recall (May have been 10-15 years ago, I'm getting old.) Price for SA-107 showed as over $2,000! You could get a new custom cell done cheaper by ATL or other builder.

Durango_Boy

Why so apocalyptic? Didn't the seller already say he was thinking of removing it and just wanted to know what material it was? To me it seems he already knew what directions he could go in.

Twist it if you like...you always do.

So...where's the data...what year did the Corvette start getting the bladder?

1nicecorvette

okay before thise all gets into more drama . for my own information can someone tell me when the cars started to NOT have a fuel tank bladder?

Durango_Boy

I'm pretty sure the bladder was removed from the Corvette tank for the '78 year where it was replaced with a harder coating inside the tank that I don't think is removable. I don't know that it was for crash protection though since I think it would just break and shatter in the event of a rear end collision...however I don't know much at all about the '78 thru '82 tanks so I have no idea what the purpose of that extra layer was.

Jim Shea

I know that the bladder was first installed in the 1975 Vettes. I am sure that it was used for the next several years. I had understood that no service bladders were available because no one would accept the liability for a failed part. I guess that you could say that a 75 without a bladder was the same as any 1969 through 1974 Vette.

Probably of more significance is keeping an inflated spare tire in the tub. The inflated spare provides energy management in a rear collision. It is probably more dangerous to drive around without a spare in the tub.

Jim

Paul L

The case history of the Chevrolet Corvette is particularly instructive. In 1975 the Chevrolet Corvette was unable to meet FMVSS 301 and not leak more than one ounce of gasoline a minute after a 30 mile per hour rear end moving barrier crash. GM's solution was to introduce a rubber bladder which provided the necessary protection against gas spillage inasmuch as the tank is located in the crush zone approximately 8 inches from the rear bumper. The history of bladders in competition race cars and in aircraft has been well documented with a variety of problems: deterioration, condensation, folding, cracking and the like. General Motors in 1978 introduced one of the safest gas tanks in the U.S. in its Corvette line by replacing the problematic rubber bladder with a High Density Poly-Ethylene ["HDPE"] liner.

HDPE is a common material for gas tanks today and an overwhelming number of safely positioned tanks on the road today are made of this plastic. It is capable of taking heavy blows and is slow to burn. It has proven itself as an automotive construction material in a number of applications.

Because the gas tank on the Corvette is directly in the crush zone for a rear impact, General Motors engineers encapsulated the HDPE tank within a standard metal tank and created a double-walled tank that has performed extremely well since 1978.

Based on the absence of fire claims from rear-end collisions suffered by Corvettes, and the vehicle's ability to be repeatedly certified by General Motors in compliance with FMVSS 301 for every production year since 1978, there is good reason to believe that a similar style HDPE/metal tank would enhance fuel system integrity of GM pickups with side saddle tanks.

General Motors's internal crash testing records indicate that an HDPE liner within a metal tank can provide a substantially higher level of protection than now exists.

Ref.: http://www.consumerlawpage.com/artic...k_safety.shtml

Durango_Boy

Wow Paul, great information. Shame the '78 thru '82 tanks won't fit in the earlier C3s.

1nicecorvette

yeah good info now i can tell what i have in there and working with!