Topic: Fuel tank strap bolt

[Scott302]

I am looking for the length of the strap bolt.  Only looking for known original bolts to be used.  Since this is a carriage style bolt the length is measured from under the head.
Regards,
Scott

[jwc66k]

Carriage bolt 384673-S100 is a 3/8-16X4 1/4 Carriage bolt, Ref "73 Mustang Chassis Assembly Manual" pg58 (there is no 71 or 72 version), and "AMK Guide to Ford Fasteners" pg 85.
You realize that NPD sell both reference books - 
Jim

[krelboyne]

Did not realize that this was already partially answered.

Additionally they are grade 5. Fairly tall square shank, of 3/8" under the head. 3/8-16 Hex flange nuts, for attaching.

AMK lists B-12744, for the Mustang gas tank straps, but it is only 4.0 inches long, and has a shorter square shank under the round head. Page 8 in the 2014 fastener catalog.

[jwc66k]

AMK lists B-12744, for the Mustang gas tank straps, but it is only 4.0 inches long, and has a shorter square shank under the round head. Page 8 in the 2014 fastener catalog.

This is being addressed by Scott at NPD and AMK.

Additionally they are grade 5.

The AMK "Guide to Ford Fasteners" (pg85) does not list a grade. I have two from salvaged cars that are grade 2.
In addition, the diameter of the head is 13/16 inch.
Jim

[67gta289]

According to what I'm seeing in the MPC world, this is one of those times when a fastener has what I would call a "traditional part number" instead of the style typically used for fasteners.  I'm seeing C8AZ-9A010-A with specifications 3/8"-16 x 4-1/4" carriage bolt.

Jim's reply #2 identifies the fastener part number of 384673-S100, referenced in the 73 assembly manual, with the same specifications as the MPC.

If you look at the 65-72 MPC text picture, you will see a wide range of models and years.  Broadening the search might help.  Of course, a C8 part number on the 65/68 Galaxie and the 67 T-Bird is indicative of what happens in the service arena.

I've got a friend near me that has stripped several 67-68 T-Birds so I'll ask if he has any.  Chances are though that something like this ended up in the scrap metal bin.

[jwc66k]

According to what I'm seeing in the MPC world, this is one of those times when a fastener has what I would call a "traditional part number" instead of the style typically used for fasteners.  I'm seeing C8AZ-9A010-A with specifications 3/8"-16 x 4-1/4" carriage bolt.
Jim's reply #2 identifies the fastener part number of 384673-S100, referenced in the 73 assembly manual, with the same specifications as the MPC.

Remember, it's a service number, which will work as a replacement, but may not be the same as what was used on the assembly line. One of Ford's overall service department policies was to reduce the number of items on the shelf.
Jim

[67gta289]

Agreed.  That is also the case with 384673, and even more so the case with a year 2021 AMK replacement

[Scott302]

Thanks for the input all.  I knew what the Ford books said it was supposed to be.  I wanted a measurement from a correct bolt.  Jim (JWC66K) not only gave me the measurement but the head marks too and is now sending a few of his samples to AMK.  AMK was supplying the wrong length bolts and they will use the samples Jim is supplying to make it right. 
Regards,
Scott

[jwc66k]

And it's been fun, informative and interesting.
Jim

[specialed]

Max at amk is aware of this bolt being too short as i told him last month when we were working on a 71 mach1  we just cleaned original bolts and used over. Another problem is the carb stud lenght  as depending on the air filter height fa41 vs fa50 example the fa 50 is taller so u need a longer carb stud.  Sometimes max has to use whatever hardware he has in stock  that he thinks may work and if restorers dont get back to him he dont know there is a fitment problem and also  some of his hardware supply is limited and goes obsolete then he has to try and find something else that will work and thats why some of his hardware has different  vendor markings.