Topic: Horn wire length coming through the radiator support

[sgl66]

Haven't been able to find anything on this topic but it appears that Ford changed the wire length during 66?

I recently had my horns rebuilt and the passenger horn had a large nut holding the bracket with a FoMoCo logo on it. Gary at The Horn Works said this is what Ford used when servicing horns. When and how that made it onto the car is unknown but he put the correct bracket on and when I went to install the horn, the connector for the wire is now around 4 o'clock when looking straight on instead of 8 o'clock where it used to be.

Back in the 80's I replaced the wiring harness with a new one from Ford and never thought about it again. I pulled my OEM harness out of a storage box yesterday and the wires for both horns are 2 1/2" longer which explains why the replacement harness doesn't fit.

I looked through the unrestored threads and found a few examples of the longer wire going to the 4 o'clock position and at least for a December 65 Dearborn car the connector moved to the 8 o'clock position and what appears to be a shorter horn wire with the 65 style bracket. My best guess is Ford did some math on what saving 7 1/2" of wire per car would add up to by simply moving the connecting point on the passenger side and reducing unneeded wire on the drivers side.

Curious if there are any other examples of when the connector location changed on a horn with the 65 style bracket, and whether it was a very small window of time or if different suppliers produced them both ways up until the bracket change?

[midlife]

I've never noticed any wire length changes, primarily because I haven't had a need to do so.  Your problem is the first I've heard about, but not all that surprising, since I typically recommend reproduction harnesses in the engine bay for 65/66 models.  Even so, I focus upon the wire functionality and not its length unless it has been previously cut.

I wonder if your horns are reversed left/right and if so, can they now fit? 
There's not a good way of splicing horn wires for concours-level judging without the splices showing.
Mid

[jwc66k]

Looking at the 1965 and 1966 Mustang Electrical Manuals, the "bells" of the horns are in a relatively straight line with the mounting bracket. Both my 65 SJ GT Fastback (May 11, 65) and 66 SJ GT Fastback (Oct 18, 65) are like that. Your horns look like 1967 Mustang horns, the "bells" are at a right angle (almost) to the bracket. Like Randy suggested, reverse them.
Jim

[sgl66]

Flipping the horns was my first thought but that definitely isn't the answer because then the passenger bell is facing up.

The drivers side horn fits fine and doubt it's a 67 because it has the 65 bracket.

The two 65 images I copied from the unrestored cars section do not have the bracket and bell in a straight line and my passenger horn bolts on identical to those, it's just that the wire is 2 1/2" too short. The December 65 image does appear in more of a straight line which moves the brass connector to the other side so it can work with the shorter wire.

Here's another one from a different thread with a better view. Not sure of the build date or plant  https://www.concoursmustang.com/forum/index.php?topic=9004.msg52752#msg52752

[jwc66k]

Take a look in this Forum's Library in Ford Car Parts (aka MPC) in section 13, Lighting, in base number 13832/3 for "replacement horns". The replacement are a "kit", C7AF-13802-A (low) or -B (high) with a lot of adapter brackets.

Gary at The Horn Works said this is what Ford used when servicing horns. When and how that made it onto the car is unknown but he put the correct bracket on and when I went to install the horn, the connector for the wire is now around 4 o'clock when looking straight on instead of 8 o'clock where it used to be.

That may be your problem. You got rebuilt horns to a service specification but without the adapter brackets.
Jim

[sgl66]

Take a look in this Forum's Library in Ford Car Parts (aka MPC) in section 13, Lighting, in base number 13832/3 for "replacement horns". The replacement are a "kit", C7AF-13802-A (low) or -B (high) with a lot of adapter brackets. That may be your problem. You got rebuilt horns to a service specification but without the adapter brackets.
Jim

Thanks Jim

Gary rebuilt it for me using a correct 65 housing/bracket from his cores and ditched the replacement parts.

I also just figured out that by attaching the wire before bolting the horn to the radiator support gave me just enough slack to bolt it on with the shorter wire.

For future reference, this is how I measured the service replacement wire. The OEM wire is 2 1/2" longer

[midlife]

Now my curiosity is piqued!  i went to my stockpile, and measured the length from the groove in the grommet to the tip of the connector: 5" in one harness and 9" in another!  You do say???For what it is worth, NPD does list 2 versions of the 66 headlight harness: before 11/15/65, modify as required, and after that date.  All these years, I've never noticed an ELECTRICAL difference in the headlights, but maybe the horn length and associated bracketry might be one reason for the change.From your PM, you appear to have the earlier version. 

[jwc66k]

Here's a couple of pictures of C5AF-13801-B, the "HI" pitch horn that goes on the left hand side of the radiator support.
The red arrows point to the raised letters indicating pitch, in this case "HI", and marked in two places. FOMOCO in the rectangle on the exposed side, in an oval in the bracket. I believe there may be additional markings using a stamp in white ink.
Note the straight line the mounting bracket makes down to the "bell" of the horn. The horns on my 65 GT Fastback are the same, the straight line.
The two wire power lead, from the radiator support to the tip of the insulator on the spade tip receptacle, is 6 1/2 inches long. This is an Oct 18, 1965 San Jose build, and I have no reason to suspect the feed harness was replaced.
(A quick dusting, and back in it goes.)
Jim

[J_Speegle]

Are we getting a mixture of 65 examples in the discussion (both of the later versions) and affecting the observations and data offered here?

[sgl66]

Are we getting a mixture of 65 examples in the discussion (both of the later versions) and affecting the observations and data offered here?

Yes, the horns Jim is showing have the 66 style bracket which was a running change. https://www.concoursmustang.com/forum/index.php?PHPSESSID=d97t31057mg9p0k4qqi3pfbs87;topic=19184.new#new

Jim, my horns have the same Hi Lo and FoMoCo casting/stamps. The service replacement horn Gary replaced was held to the bracket with a 7/8" nut. OEM horns had the bracket riveted to the housing. Image on the blue towel shows the driver and passenger horns I pulled off. The other image is the passenger horn Gary rebuilt with the correct parts.