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1968 Mustang Fast Back (gas nozzle)

I am in the ending stages of restoring a 1968 mustang fastback. Now that it is road ready, I am having trouble fueling her. The nozzles at the gas stations do not make a secure seal, and gas leaks into the car and ground. Is there any thing that can be done to fix this probelsm?

What do you mean, gas leaks ‘into the car’? Into the trunk? There should be no way for that to happen.

Try putting RTV silicone around the area its leaking. That will provide a seal that gas can’t penetrate.


Where exactly is it leaking? Under what conditions?

In many Fords of this era, the floor of the trunk was the top of the gas tank. Is this the case with your Mustang? This arrangement used to cause the problem you are having.

Pull that trunk liner up and inspect the filler neck and top of the gas tank for leakage…

Yep, that’s what he’s got. Might be a bad clamp, or aged/cracked rubber hose from the filler to the tank.

Old Blue, it’s not the new gas station nozzle causing the problem. You need to find the source of the leak, this is a safety issue. There’s no barrier between the tank and the passenger compartment (don’t get rear ended!).

Thank you for confirming my suspicion about the Ford gas tanks of this era. I remember seeing a mechanic replace a tank that had been punctured by an object in the trunk in a 1963 Ford Falcon. I had a 1971 Ford Maverick and the gas tank was separate from the trunk floor. I checked before I bought the car–I wouldn’t have purchased it had the top of the gas tank been the trunk floor. I think even Consumer Reports commented on this dangerous design. When did Ford finally abandon this bad design? I know it had to be before 1971.

Not sure, but I do know the tank on your 68 is pretty much the same as the one on the 65 I had years ago. That tank did have the (small) advantage of easy replacement, which I had to do in a donut shop parking lot after my brother punched a hole in it…