Topic: 1970 Mach1 gas cap conversion F3ZZ-9030 doesn't fit fill tube

[jvlandy]

I have a 1970 Mach with (what I believe to be) the original gas tank filler tube in excellent condition.  The original flip down is very good also.  However, I wanted to use the F3ZZ conversion cap for safety reasons.  When I tried to install twist on the cap, it doesn't even come close to sealing.  It has a huge gap between the new seal on the cap, and the surface of the fill tube.  It doesn't even catch the stops on the inside of the tube, and goes right over them.  Photo attached.  Anybody ever see this before?  Thanks in advance for any help.  -Andy

[krelboyne]

Might that be a 1993 gas cap?

[jvlandy]

While the part carries a 1993 number, it was released by Ford specifically for 1967-1970 flip down gas caps.  I know others have used this update kit and I'm wondering if they ran in to this situation.  I tried using double gaskets, but still a very big gap exists, and will not tighten.  Thanks for the reply.

[jwc66k]

The Ford service stock number is F3ZZ-9030-F. You neglected the "F" in your post. A search on duckduckgo dot com (I don't like Google) shows several other options, and a few additional questions and confusion. If you can, return the cap.
Jim

[jwc66k]

In addition to my previous, there are two filler pipes used on Mustangs in 1970, D0ZZ-9034-A used without smog, and D0ZZ-9034-B used with smog. Because of that, there are two caps used, D0ZZ-9030-D with smog, and D0ZZ-9030-E without smog. Those stock numbers are listed in 1975 "Ford Car Parts" (aka MPC) book. I do not have a cross reference to current numbers. I'm not saying that's an answer, but it "may" be.
Jim

[jvlandy]

The Ford service stock number is F3ZZ-9030-F. You neglected the "F" in your post. A search on duckduckgo dot com (I don't like Google) shows several other options, and a few additional questions and confusion. If you can, return the cap.
Jim

Sorry, I neglected to add the -F (shown in my photo though.)  This was a sealed box, and the direction sheet specifies 67-70 Mustang, and illustrates the flip down gas cap.  Weird that it doesn't come close to fitting.  I bought 2 boxes, both identical contents, a few years ago.  I took some additional photos. -Andy

[jvlandy]

In addition to my previous, there are two filler pipes used on Mustangs in 1970, D0ZZ-9034-A used without smog, and D0ZZ-9034-B used with smog. Because of that, there are two caps used, D0ZZ-9030-D with smog, and D0ZZ-9030-E without smog. Those stock numbers are listed in 1975 "Ford Car Parts" (aka MPC) book. I do not have a cross reference to current numbers. I'm not saying that's an answer, but it "may" be.
Jim

Thanks for the added info.  This was a Wisconsin car, so not a smog car.  I'll need to follow up on your info. -Andy

edited: Actually, the 9030-D is the non-flip down, large Standard Chrome Mustang twist-on, with emissions, while the 9030-E is the whole flip-down assembly.  The 9030-F was the safety upgraded cap only, released in 1993.  Still, not certain if the fill tube is the difference.  Thanks again!