ConcoursMustang Forums

1st Generation 1964 1/2 - 1973 - Questions & general discussions that apply to a specific year => 1967 Mustang => Topic started by: Kyle Zammit on August 16, 2023, 05:59:27 PM

Title: Ignition switch ground strap bracket (screw type ?)
Post by: Kyle Zammit on August 16, 2023, 05:59:27 PM
Hi all,

I am looking for information about these two types of screws for the ignition switch bracket.
Here is a picture showing the two types of screws. Not shure if the philps head were used on 67 Mustangs and 67 Shelbys

Thanks Kyle.
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: jwc66k on August 16, 2023, 07:45:30 PM
Did you look in this forums' library under topic "Mustang Hardware Spreadsheet 67-68"? Just asking.
Jim
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: J_Speegle on August 16, 2023, 10:30:08 PM
Hi all,

I am looking for information about these two types of screws for the ignition switch bracket.
Here is a picture showing the two types of screws. Not shure if the philps head were used on 67 Mustangs and 67 Shelbys

Thanks Kyle.

You asking about San Jose specifically?
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: Bob Gaines on August 16, 2023, 11:32:11 PM
Hi all,

I am looking for information about these two types of screws for the ignition switch bracket.
Here is a picture showing the two types of screws. Not shure if the philps head were used on 67 Mustangs and 67 Shelbys

Thanks Kyle.
The hex screw was typical on 67 Shelby's/SJ Mustangs .
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: Kyle Zammit on August 17, 2023, 01:29:01 AM
Yes I am looking for San Jose Specifically.
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: J_Speegle on August 17, 2023, 04:22:57 AM
Here is a close up from an unrestored 67 San Jose Mustang with a VIN just over 7R200xxx


Can't make out the head markings fully looks like it possibly is the one marked CF on the head like the one in your picture. On a GT Mustang the screw also secured the bracket the grill light switch was mounted in also as shown in the picture. Got lucky and had this picture.

(https://www.concoursmustang.com/forum/gallery/19/6-170823032139-19077779.jpeg)

Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: Bob Gaines on August 17, 2023, 11:15:41 AM
Here is a close up from an unrestored 67 San Jose Mustang with a VIN just over 7R200xxx


Can't make out the head markings fully looks like it possibly is the one marked CF on the head like the one in your picture. On a GT Mustang the screw also secured the bracket the grill light switch was mounted in also as shown in the picture. Got lucky and had this picture.

(https://www.concoursmustang.com/forum/gallery/19/6-170823032139-19077779.jpeg)
CF is one of a couple typical head markings I have seen used there. 
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: Bob Gaines on August 17, 2023, 11:18:11 AM
The bracket is typically unpainted bare steel when I have observed it.
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: Kyle Zammit on August 17, 2023, 12:25:41 PM
Thanks for all the information. I Have two brackets they are bought bare steel. The one with CF screw was removed from a 67 Mustang  SJ built Nov 1966 and the other one with Phillips screw was removed from a 67 Shelby SJ built Dec 1966.
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: Bob Gaines on August 17, 2023, 02:44:34 PM
Thanks for all the information. I Have two brackets they are bought bare steel. The one with CF screw was removed from a 67 Mustang  SJ built Nov 1966 and the other one with Phillips screw was removed from a 67 Shelby SJ built Dec 1966.
Since the Phillips screw is not called out in the engineering drawings as typical the indication would reasonably be that it is ether a seldom used alternative or a replacement . If seen while judging and I noticed it I would need some kind of reasonable proof that it was original to the given car . That is because of the out of the ordinary usage. That is just me.
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: Kyle Zammit on August 17, 2023, 05:06:18 PM
Ok thanks to all for helping me. I will do the CF hex screw. Thanks for everything!
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: Bossbill on August 18, 2023, 07:38:19 PM
For those wondering, it's item 11 in this pic (screw 55907-S2).
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: jwc66k on August 19, 2023, 08:03:35 PM
I will do the CF hex screw.
For those wondering, it's item 11 in this pic (screw 55907-S2).
Not so fast.
First: 55907-S2 is documented (AMK Guide - pg149) as a 8-18X1/2 HH, Washer, Type AB (looking for the defination of Type AB vs a Type A, it may be threads per inch, or tip) with a 1/4 inch hex drive (I measured it). It is identical in dimensions to 373611-S (they are on the same AMK page next to each other). I have a container of 8-18X1/2 HH screws (over 50) and NONE have a CF head marking - REPEAT - none. Most have Type 30 head marking (see attached). Most of the hardware I have came from salvaged Mustangs that were built in Milpatas, aka the San Jose plant.
Second: The most common CF marked head screw I have seen is 42127-S, a 10-12X1/2 HH, Washer, Type A (see above, same AMK Guide page - get a copy). It has a 5/16 inch drive. Note the difference in screw diameter and drive.
Third: On the assembly line, a worker uses a power driver to install screws. You can cram a size 10 screw into a size 8 hole. I'm not saying that was done, but it could have happened.
Fourth: A picture does not give dimensions plus type (diameter, threads per inch length and tip). Keep that in mind.
Jim
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: J_Speegle on August 19, 2023, 11:11:22 PM
Did get a chance to look at a few unrestored 67 San Jose examples in the last few days and since this subject came up I did look at this details while I was looking over the cars. Each had the same hex headed screw with the CF markings on the head.  As an aside and since Jim brought it up I also have a collection of hardware just about 90% from San Jose built cars and have a fair number of CF marked hex headed screws but I can't report, without going through buckets their exact length or size.

Jim not sure what the page from AMK's publication was for but sure you had a reason. Easy to see that it doesn't represent all of the companies or head markings found originally on our Mustangs and Shelby's   :)
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: jwc66k on August 20, 2023, 03:42:55 PM
Each had the same hex headed screw with the CF markings on the head. 
It's the size that is the question, and the only visible difference available is the drive size of the hex head screw.
..  I also have a collection of hardware just about 90% from San Jose built cars and have a fair number of CF marked hex headed screws but I can't report, without going through buckets their exact length or size.
I went thru a container of around 50 55907-S2 screws and none had a CF (AMK Type 6) head marking. (Wanna play the "Lotto"?)
.. not sure what the page from AMK's publication was for but sure you had a reason.
The majority of screw heads I have for 55907-S were marked with AMK Guide Type 30 - an "O".
Another page is attached from the AMK guide, pg 149 (third edition, my 1st edition is marked up with way too many notes), showing measurements for 55907-S and 373611-S (plus 376386-S which is shown as stainless), plus 42127-S, the most common screw I have found marked with a CF head (also marked with "FC" in the same font, plus "RBW" and a few others). Note: the drive size is omitted in the AMK guide on this page. I measured the drive size as 1/4 inch hex for size 8 screws, and 5/16 inch hex for size 10 screws.
Screw 55907-S is shown in the latest AMK catalog I have (2019 Bulk) on pg 79 with an "A" in two circles head marking.
To Kyle; Measure the screw you currently have installed and report it's measurements.
Jim
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: jwc66k on August 22, 2023, 06:10:56 PM
If I can impose on a forum member or two with a 1967 or 1968 Mustang to do a "sanity check" on that screw in question. It's a simple request, take a 1/4 inch hex socket and a 5/16 inch hex socket and see what size drive the screw that retains the ignition switch retainer is. It's located to the right of the steering column under the dash and directly under the ignition switch. That measurement will give a "clue" as to the screw size.
Thanks,
Jim
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: TLea on August 24, 2023, 08:33:03 AM
Never seen 67 or 68 from any of 3 plants with 5/16 hex. Different head markings but always 1/4
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: jwc66k on August 24, 2023, 02:18:57 PM
Never seen 67 or 68 from any of 3 plants with 5/16 hex. Different head markings but always 1/4
Tim,
Thanks. That hex size lends credence to the screw being a size number 8.
Jim
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: TLea on August 27, 2023, 01:09:19 PM
 :)
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: TLea on August 27, 2023, 01:10:43 PM
, I have seen CF, one with concentric circles and another with a triangle in the middle. The CF is by far the most common.
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: Kyle Zammit on August 27, 2023, 05:47:50 PM
Thanks to all for the information!
Os there is a picture of the CF with triangle in the middle please?
Title: Re: Ignition switch ground strap bracket (screw type ?)
Post by: J_Speegle on August 27, 2023, 07:52:41 PM
Thanks to all for the information!
Os there is a picture of the CF with triangle in the middle please?

Believe (which matches what I've seen) there are three versions he is referring to

Center head markings of these screws for different years, plants and applications '

1- CF
2- Concentric circles
3- Triangle

There are similar screws with Diamonds but not going to add that in to create confusion  ::)