72 RR Horn

[BlackGTS]

What side does it mount on and what color is the wire going to it?

Thanks,Dave

[71440 gtx]

It goes on the passenger side, front rad cradle and it should be a black wire. If it's a roadrunner, if it's a satellite it goes on the other side bolted to the fender, in front of the rad cradle. I could be wrong, it's been awhile since I hooked one up. In '71 it's totally different, it goes on the inner fender.

[72RoadRunnerGTX]

The 72’ RR horn was bolted to the fender behind the headlights and in front of the radiator core support on the passenger side. Within and inch or two of the hood pin mounting location. The two holes (bolt hole and the smaller locator hole) were not present on the 71’ fender, as it was previously mentioned; the horn was mounted to the inner fender behind the core support on the 71’s. FYI, the standard dual horns were bolted to the core support, one on each side behind the headlights on the Satellites.
The forward lighting harness should contain the female spade connectors for the horns behind the headlights, both sides. The RRs used the right side only as it was paralleled off the left side. Black sounds like the correct color to me as well.

[moparmarks]

Heres a shot of an old 72 RR that I had.

[72RoadRunnerGTX]

Just took a look at that wire color, if you rub that 35-year old “black” off it reveals a green/red traced wire.

[72Rdrnner]

Deleted to save pix space

[72RoadRunnerGTX]

That is strange, I took another look at all my 72’s and can’t find any horn mounting holes in the upper core supports that would correspond to how your horn is mounted. My first post indicated I had found the Sat horns mounted to the core support, not so, they were bolted to the fender braces. The 72’ fenders have two sets of mounting holes (bolt hole with a second smaller locating hole) in each fender; one of my Sats has a 71’ fender having only one set. My RR does have a hole on the left side core support that conceivably could be used to mount a horn but can’t find any evidence to indicate that any thing had been mounted there. The only way I could get my RR horns to fit as yours would require reversing the bracket. The bracket on my original and replacement horns are mounted to the horn 180 degrees from your bracket. My RR did have A/C (engine compartment components long gone) as do both my Sats, as shown there is an A/C line on the one Sat that is routed over the top of the core support that would directly interfere a mounting such as yours. I see that yours is routed through the core support.
Having the car since new would carry a lot of weight with me. Could there have been two factory locations for the Road Runner horn in 72’?

[72RoadRunnerGTX]

Satellite A/C line.

[BlackGTS]

Mine is also located on the driver"s side on the radiator(core) support.My reason for asking the question was I got new harnesses from Year One and I couldn't find a horn wire.My problem ended up being the engine harness is for a 72 so no horn wire in it.The forward light harness is for a 71 so no horn wire in it.I first got a 72 forward light harness but the parking light plugs were different so I returned it and got the 71 harness.I must have 71 parking lights as they have the 2 prong plug whereas the 72s must have a 3 prong plug.I kept my old harness and the horn wire is green with aa red tracer and the parking lights are 3 prong.

[72Rdrnner]

That is strange, I took another look at all my 72’s and can’t find any horn mounting holes in the upper core supports that would correspond to how your horn is mounted. My first post indicated I had found the Sat horns mounted to the core support, not so, they were bolted to the fender braces. The 72’ fenders have two sets of mounting holes (bolt hole with a second smaller locating hole) in each fender; one of my Sats has a 71’ fender having only one set. My RR does have a hole on the left side core support that conceivably could be used to mount a horn but can’t find any evidence to indicate that any thing had been mounted there. The only way I could get my RR horns to fit as yours would require reversing the bracket. The bracket on my original and replacement horns are mounted to the horn 180 degrees from your bracket. My RR did have A/C (engine compartment components long gone) as do both my Sats, as shown there is an A/C line on the one Sat that is routed over the top of the core support that would directly interfere a mounting such as yours. I see that yours is routed through the core support.

Having the car since new would carry a lot of weight with me. Could there have been two factory locations for the Road Runner horn in 72’?

Went back and dug into my library of pictures, as well as took a good close look at the front top fender area (where the fenders attach to the radiator core). Found some things even I had forgotten about.

1. The original horn mounting might have been turned around so the horn would fit below the stock a/c line that came up the driver side to the condenser. I put a new condenser in when I changed to a Sanden compressor and R134. Due to the fitting being about 1/2 inch lower I made a new hose/line that came through the square opening in the radiator frame not over the top as it was stock. (I found a pix of that) So I was able to mount the bracket on the other side of the horn which made it stick up higher, something it could not do with the stock a/c line. But I still used the two holes that were in the radiator support.

2. I checked my fenders and all the requsite holes are there on both sides.

3. I double checked the old stock front wiring harness and in fact the only horn wire I can find is on the driver side. The wire to the horn is dark green with a red tracer, a single wire that terminates at the horn connector. Looking in my FSM Body manual there is only a front wiring diagram for the Satellite, not a Roadrunner specific one. It shows a second dark green with red tracer wire for the second horn. The Year One harness I have does have a second wire going to the passenger side horn also dark green with a red tracer. (edited as I originally missed seeing the tracer as the wire was wrapped up and not exposed)

It appears this is one of those great mysteries of the old days when assembly lines were less mechanized, and more human element was used. When the worker got ready to put my horn in he discovered there was no wire on the passenger side went to the other side. Why he didn't use the fender holes and mounted it on the radiator frame is a mystery. It looks like he turned the horn around to clear the a/c line, or if that was not there, just mounted it and let the a/c line assembler worry about it, in which case that worker turned the horn/bracket around! Called Yankee Ingenuity!

Actually I kind of like it as it puts that beautiful purple horn up where it can be seen…and heard! BEEP, BEEP!

One other thing. I don’t remember the voice of the roadrunner decal on my horn. (however that was many years, and many beers ago) It is possible it had fallen off by the time I took the horn off although the pix of the horn before I painted it doesn’t show evidence it was ever there…like some discoloration.

All in all I think it points to how there were “warts” on the cars that made each one unique, which begs the question of how a judge comes to the conclusion of what is “factory specs”. Seems like the “wart factor” is one that can never be fully integrated into the precision of restoration.

So now I am in a REALLY BIG QUANDRY!

Some Saturday night, while parked at the local Sonic Drive in, with a few of my local Mopar club friends and our cars, hoods open, displaying our pride & joys, someone walks up and loudly proclaims in an all knowing way, (peering into my hood),

“Your horn is on the wrong side!”, should I

1. Politely and humbly thank him then immediately get out my tools and move the horn? or

2. Slam the hood on his head?

Enquiring minds and all that! Woo Hoo!

[72Rdrnner]

Mine is also located on the driver"s side on the radiator(core) support.My reason for asking the question was I got new harnesses from Year One and I couldn't find a horn wire.My problem ended up being the engine harness is for a 72 so no horn wire in it.The forward light harness is for a 71 so no horn wire in it.I first got a 72 forward light harness but the parking light plugs were different so I returned it and got the 71 harness.I must have 71 parking lights as they have the 2 prong plug whereas the 72s must have a 3 prong plug.I kept my old harness and the horn wire is green with aa red tracer and the parking lights are 3 prong.

You are quite correct about the parking lot connectors. '71 (and perhaps earlier) had a two prong male/female rubber connector. "72 (and perhaps later) had a 3 wire plastic connector. My '72 parking/turn lights have three wires as the bulbs have two filaments, one for the parking light and the other for the turn signal. I guess the '71s used a single filament for both.

As for no horn wire on the ’72 harness from Year One…that’s got me stumped. The one I got from them not only had a horn wire, but one for each side. Plus it had the additional wires for the fender mounted turn signals, something my car did not have.

FWIW I checked my receipts and the harness I got from Year One was HU243B which is also the number in their current catalog on page 102 under Forward Light Harnesses as “1972 Plymouth and Dodge without concealed head lights and with fender-mounted urn signals”.

[72GY9Runner]

Just to chime in on this topic.

I too have a 72 Runner with A/C, and my horn was also mounted on the drivers side with a bolt thru the rad shell. The wire harness in my car is original and has horn wiring on both sides of the car, but the passenger side horn wire had been wrapped into the tape and was unuseable. The harness had not been re-taped, and was still using the original no-stick wrapping, but someone had actuall wrapped the second wire right up in the harness.

Just for reference this was a Canadian built car.

Dave

[mopar71]

72rdrnner, where was your car built?

[72Rdrnner]

Just to chime in on this topic.

I too have a 72 Runner with A/C, and my horn was also mounted on the drivers side with a bolt thru the rad shell. The wire harness in my car is original and has horn wiring on both sides of the car, but the passenger side horn wire had been wrapped into the tape and was unuseable. The harness had not been re-taped, and was still using the original no-stick wrapping, but someone had actuall wrapped the second wire right up in the harness.

Just for reference this was a Canadian built car.

Dave

Thanks for the info. I'm going to go back and do a closer examination of the wiring harness. The repo harness has two wires running to the driver's side horn, one of which is the one that goes over to the right side. The original only has a single wire to the driver's side horn, but the junction for the passenger side might be inside the wrapping, so I'll just go take a peek.

Like looking for buried treasure.

[1972RM23]

My horn is on the drivers side too.