Author Topic: Correct screws to mount 1970 Mach 1 pop-open gas cap?  (Read 4371 times)

Offline Cobrajet428

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Correct screws to mount 1970 Mach 1 pop-open gas cap?
« on: June 11, 2012, 02:30:42 PM »
My question is about the correct screws to mount a 1970 Mach 1 pop-open gas cap. There are a total of 5 screws that mount the cap to the tail light panel. Four of these go from through the cap assembly into the panel and one goes from inside the trunk, through the panel, and into the cap assembly. The Osborn 1970 Mustang Chassis Assembly Manual has a page showing the cap mounting to the panel, but only illustrates the 4 screws that go from outside, NOT the screw that goes from inside the trunk into the cap assembly. It shows something going from inside-to-out, but I believe that to be a cable retainer for a different model, not used with this cap assembly. AMK's screw kit only contains the 4 outside-to-in screws, so that doesn't help resolve the question of the 5th screw.

Could anyone provide a photo or point to a different drawing that identifies just what screw is to be used for this 5th screw? I'm attaching a photo from my car as reference - it's the zinc dichromated (gold) screw) shown and as it's both hex and phillips screw head, I'm almost certain it's wrong.

As well, the 4 screws that run from outside into the trunk are shown in the AMK hardware book as having flat, not pointed tips. Can someone also comment as to whether the flat-tip type are correct (as used originally) ?

My car is Dearborn-bult Oct. '69, but I'm also asking for a friend where I'm not sure of the build origin. If there's a known plant difference, feel free to point that out.

Offline Cobrajet428

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Re: Correct screws to mount 1970 Mach 1 pop-open gas cap?
« Reply #1 on: June 18, 2012, 01:45:13 AM »
C'mon now ... there's got to be another '70 Mach 1 owner here with original gas cap screws ... how about a photo or good description of what's on your car?

Offline Brian Conway

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Re: Correct screws to mount 1970 Mach 1 pop-open gas cap?
« Reply #2 on: June 18, 2012, 04:54:01 PM »
I know your asking about the 70 model but here is some info on a NJ 69 Mach 1.  Out to in;  4 Flat head Phillips head machine screws and flat not pointed .  The in to out; is a threaded post with a 1/2" nut.  The nut has a captured flanged washer.  Can't swear that's OE but that's whats on the car.  Brian
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Offline 1970 SCJ

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Re: Correct screws to mount 1970 Mach 1 pop-open gas cap?
« Reply #3 on: June 19, 2012, 07:44:30 PM »
On my 12/69 Metuchen they are the same as Brian described.

Don

Offline Cobrajet428

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Re: Correct screws to mount 1970 Mach 1 pop-open gas cap?
« Reply #4 on: June 20, 2012, 01:29:40 PM »
Thanks! I sure wish the engineering drawing showed that threaded stud/nut used near the bottom right. I've got no idea where to get the right parts (AMK mount kit only has the 4 flat-tip screws), but at least I know now what they look like!

Offline Cobrajet428

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Re: Correct screws to mount 1970 Mach 1 pop-open gas cap?
« Reply #5 on: June 21, 2012, 01:06:18 AM »
Hey, just had a thought ... Brian Conway showed the same hardware used on the '69 pop-open cap. As I'd mentioned, the '70 Mustang Chassis Assembly Manual drawing didn't show the stud/nut w/washer parts that are inside the trunk. Perhaps the '69 drawing shows this.

Could someone (Brian?) here with a set of '69 manuals copy the drawing that shows the pop-open cap hardware, or at a minimum provide part numbers for the stud and nut w/washer from that drawing?

Offline Brian Conway

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Re: Correct screws to mount 1970 Mach 1 pop-open gas cap?
« Reply #6 on: June 21, 2012, 02:23:11 PM »
Sorry, no help here.  Brian
5RO9A GT  4 Spd Built 5/29/65
9TO2R SCJ 4 Spd Built 9/19/68
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Offline sah62

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Re: Correct screws to mount 1970 Mach 1 pop-open gas cap?
« Reply #7 on: June 22, 2012, 07:48:47 AM »
Images from the 1969 chassis assembly manual attached. Part number for screws used with the pop-open cap: 52064-S8. Nut for stud: 380331-S8. This matches what's in the 1970 manual, and both are listed in AMK's "Guide To Ford Fasteners"

Is your cap missing the stud?
« Last Edit: June 22, 2012, 07:51:09 AM by sah62 »
Scott Hollenbeck
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Offline Cobrajet428

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Re: Correct screws to mount 1970 Mach 1 pop-open gas cap?
« Reply #8 on: June 24, 2012, 04:22:47 PM »
Images from the 1969 chassis assembly manual attached. Part number for screws used with the pop-open cap: 52064-S8. Nut for stud: 380331-S8. This matches what's in the 1970 manual, and both are listed in AMK's "Guide To Ford Fasteners"

Is your cap missing the stud?

Scott - thanks for the images from the '69 book. The '70 book shows the 380331-S(4) part, but it was impossible at the time for me to tell just what it was. Both the '69 and '70 drawings show this nut being used with a different cap with a cable/pin (no dashed line is shown intersecting with pop-open cap). I don't have the AMK fastener guide, but tried looking the part up in their catalog and a couple of old Ford Standard & Utility Parts Catalogs and it wasn't listed. As well, neither drawing calls out a part number for the stud - perhaps it was part of the pop-open cap assembly.

My cap is missing the stud, and I don't have the nut/washer either.