Topic: Hinge Bolt Questions - 2/6/65 San Jose

[MustangAndFairlane1867]

I am re-assembling a 1965 Mustang fastback (San Jose, 2.16.1965) that has been apart and in pieces since the 1990s. Needless to say, some parts and pieces have gone missing, the most recent being 4 of the 10 bolts I need to mount the two doors to the door hinges. I would like to find out what years these bolts were used in the assembly process and what the number 23 stands for that's on the bolt heads.  I also hope to find someone I can buy these missing 4 bolts from.  Here's a description: they have the number 23 cast on top of the bolt head; they have star washers attached; the threads are 3/8-16 coarse thread; and they are 1 1/4 inches long as measured from the underside of the star washer to the other end of the bolt. I am going to try and upload 3 pictures here and I hope I succeed because they are sharp, clear shots of the bolt. If anyone has 1 or 2 or 3 or (yahoo) 4 in their stash I could purchase, I would be most appreciative and able to move on to the next step in this fun but occasionally frustrating restoration. And any info re the history of the bolts' use on the assembly line and the meaning of the "23" on the bolt head would be helpful. Thanks, Ron:

[J_Speegle]

Have no idea what the 23 refers to. Currently head markings are understood to identify the type of bolt and or the provider/maker. Your limited on finding them only on 64-65 Mustangs  but if you look to other Ford models Fairlanes and Falcons would be worth checking out - same year

Bolts marked with the same 23 are used in other areas of the car but I don't think the bolts and specs are the same. Shock tower support attaching bolts is one of those examples.

[MustangAndFairlane1867]

Jeff:  Thanks for that interesting info.  After I read it all I looked at my "project" '65 and noticed for the first time that 7 of the shock tower attaching bolts you referenced are marked "26," but one of them is marked "23" like my hinge bolts.  The only difference is the lone 23 under the hood is 1" long, where all the 23s in my doors are 1 1/4 inch long.  So now I'm also looking for a 1" long "26"bolt with affixed star washer to use under the hood!  Where does it all end? Lol.  Thanks, Ron...

[Bossbill]

You should reference Jim's spreadsheets in the Library.
Then you can find the bolt (search for "hinge") and then search the excel for any other bolts of that number.

However, I just checked my 65 and it uses the '23' bolt in the 10 door to hinge and the 10 hinge to body locations. Although the car is a modified, I've keep the bolts in baggies and identified as to location and are currently installed.

In 67 the hinge to body is also a '23', but the tooth washer is replaced by a disc washer with small teeth. Also in 67 Jim's excel says that is the only location that uses that bolt. Also note that 67 only uses the '23' 1.4"  bolt on the body side. The door side is shorter and is a SEMS.

On edit -- the 67 bolts are 5/16x18. The '23' mark is just a vendor mark, not an indicator of thread/style/type.

[MustangAndFairlane1867]

Bossbill:  Your post was especially appreciated because it tells me the "23" bolts are correct for my car.  I was beginning to wonder if a PO had slapped them on there because they were handy, etc.  So thanks for that.  Now I've got to track down 4 more "23s" to complete the hinge-to-car and hinge-to-body factory arrangement.  BTW, can you tell me if your car is also a San Jose car and when the scheduled build date was?  Thanks, Ron...

[jwc66k]

- and they are 1 1/4 inches long as measured from the underside of the star washer to the other end of the bolt.

The standard convention for measuring screws and bolts with an attached washer (split, flat, domed, external tooth, underside toothed disc or underside smooth disc) is from the underside of the head. Also, except as noted in some Ford documentation, the lead point (aka dog tip) is included in the length.
The part number (the best way to identify any item) you need is 377919-S2, a 3/8-16X1 5/16 hex, ext lkw, lead point. A vendor head marking of "23" is unusual for this. AMK lists only "SEMS" marked heads. In my pile of hardware, the head markings I have for 377919-S2 are the "SEMS", Anchor and "26", and a few external tooth hex head with a large Phillips drive.

After I read it all I looked at my "project" '65 and noticed for the first time that 7 of the shock tower attaching bolts you referenced are marked "26," but one of them is marked "23" like my hinge bolts.  The only difference is the lone 23 under the hood is 1" long, ...

These are 377917-S2, 3/8-16X1.0 hex, ext lkw, lead point. Both type of head markings, "23" and "26", are common. In this case, leave well enough alone, make the odd one a conversation piece.
Jim

[J_Speegle]

Agree with Jim - they don't all have to match in this example

Here are some other examples of different markings on cars from other periods. Sorry they are not clearer

5R1405xx




5R1508xx




5R2007xx

[Bossbill]

[snip] . . .   BTW, can you tell me if your car is also a San Jose car and when the scheduled build date was?  Thanks, Ron...

Ron -- All of my cars and build dates are in my sig. You might not see it if you have signatures turned off in your forum profile.