&^$% horn

[MidLifer]

I put a 67-72 steering wheel in my truck (original OEM one I bought used from a board member) 2 years ago, and I have never been able to get the horn button to work right. I tried the original ring/spring/screws, a new kit, cleaning the contacts on the wheel, and tightening/loosening the screws, and if i put the horn cap on it won't actuate the horn unless I press it just right (upper right hand corner), and then at times when I turn the wheel it will actuate it automatically and I have to pull over and disconnect the horn b/c it gets stuck on.

I've tried everything I've read on the forum - is it possible that there is something wrong with the wheel? Or is it just another of the General's great designs at work here?

[Lou Boffa]

subbed

[landy]

It took me several attempts to finally get the horn on my'72 to work correctly. There are some good threads on here about how to correctly assemble the components. As I recall, the thin metal disc must be assembled in the correct direction to get the horn to work right. Do you have a diagram that shows the steps? I recall that the one in the LMC catalog was wrong.

[MidLifer]

OK, so I went out and put all the parts together like the threads say - spring with center dish out (opposite to LMC's diagram), and still no workie.

Question - should the metal ring indicated by the arrow in the photo be conductive? I shorted the post to it and it did not trip the horn relay. However, if I short the post to the steering shaft, it does. Maybe a problem with my steering wheel? Can it be fixed or am I looking at a new wheel?

[1972BlueC20]

yeah i had trouble with mine too....mine doesn't really push like a modern horn...I don't think they really are supposed to....mine only works if I push the bottom right corner....but hey it works and it never goes off unless I push it, so I aint touching it LOL

I originally couldn't get it working but what finally got it to work was getting the little pin and spring in just right, then tightening the 3 screw just so....no too lose but not too tight...

good luck, and I wish I was there to help I could probably get it for you but it's one of those things thats really hard to describe how to do

[ray_mcavoy]

Originally Posted by MidLifer

Question - should the metal ring indicated by the arrow in the photo be conductive? I shorted the post to it and it did not trip the horn relay. However, if I short the post to the steering shaft, it does. Maybe a problem with my steering wheel? Can it be fixed or am I looking at a new wheel?

No, the ring the arrow is pointing out in your pic is not part of the horn button circuit.

The spring-loaded contact pin always touches the bottom side of the round spring-metal disk. But the outer edge of that disk should only be touching the plastic part of the steering wheel and the plastic spacer bushings that surround the 3 screws, all of which isolates the disk from ground.

When the button is pushed, the center part of that disk flexes down and makes contact with the shaft/nut, completing the circuit to ground and energizing the horn relay.

[franken]

I've made a few work with random parts scavenged from various GM vehicles. Its not that hard but if I had to do it again now I'd have to figure it out again.
Both mine work fine.
If the horn goes off on its own or sticks, I'd guess you're missing some parts, like insulators or have a wrong part or two.

[michael bustamante]

it sounds like i better take a bunch of pics as i pull mine for reassembly

[MidLifer]

Thanks all. Sounds like Ray is on to something - when I put it together, even though I make sure the spring is set so that the plastic bushing goes through the holes, it isn't centered. I'll have to use a small screwdriver to center it as I tighten it down.

Then I'll put a horn button on the floor and use that instead LOL. Anyway I hope I get it working soon cuz my middle finger is getting sore...Jersey drivers...

[LockDoc]

Here's to add to what the others have said.

-
Be sure to note how the parts come out, especially the flat metal disk. It is not flat, it has a slight dish to it. It goes in with dome up. Also, the metal cup has a notch in it that matches a tab on the rubber part of the horn button, so it has to be installed in a certain position or the horn button will be off center.

The large plastic piece with the spring loaded contact goes under the steering wheel and the contact tower sticks up through a hole in the steering wheel hub. The disk is the first piece to go inside the steering wheel, then the metal cup, then the plastic retainer with the three screws. If you hold the metal cup in your hand and put the retainer down inside it you will see that the bosses on the plastic retainer fit snug inside the holes in the cup. Turn that assembly upside down and put the metal disk on it and you will see that the holes in the disk just fit over the bosses on the retainer also. That is the way it has to go together. It can be tough getting it all lined up down inside the steering wheel and keeping the metal disk in place. If the disk gets out of place and gets pinched between the steering wheel hub and the retainer, either the horn won't honk or it will honk all the time.

This is one of those procedures that is hard to put into words but fairly easy to do so I hope you can follow my rambling....

LockDoc

[franken]

Yep, its like a puzzle; not that tough, but made to be a pain in the rear.
Recreating missing parts on anything is like this.
From the intermittent or shorting, I'm wondering if the insulator ring w/ 3 holes is missing?
Also some of the parts, like the wheel and flat round spring are steel, are conductors and can rust. Rust is an insulator so maybe give it a scuff w/ scotchbrite.
I have a bunch of small parts if needed.

[davepl]

I took a lot of pics. I still struggled getting some stuff together. The 1970 shop manual supplement (I think) has a good exploded view of it that really helps. The earlier manuals show a "typical" unit that has most of the parts, but not all. And having most of the parts doesn't work well.

If you're someone else planning to take one apart, take photos clear enough to show -how- things come out, make notes, and so on. If you could post photos more easily I could post mine, but you can't. Send me a PM with your email if you think it'll help, I'll zip 'em and email them to you.

[70cst]

This thread might be of help


1970 C10 Horn Diagram

http://67-72chevytrucks.com/vboard/s...d.php?t=486632

[88Ironduke]

Originally Posted by MidLifer

Anyway I hope I get it working soon cuz my middle finger is getting sore...Jersey drivers...

Very true Jim, a middle finger in New Jersey is something you will use on a regular basis!

Paul

[D.PASSMORE]

The horn contacts under the horn button and as pictured is the negative (- / black) side of the circuit for the horn system. For positive (+ / red) side to the circuit to relay (under the dash) is a un-fused direct source coming from fuse box. The Green wire is the direct power wire to the horn (s) which are grounded to frame. When you push horn button, the thin metal disc that rides on the plastic collar inside the wheel touches the ground area (pictured), thus completing the circuit - which activates the relay, which the sends 12 VDC to horn(s), which then they sounds off. The Trick - is ensure that all contacts in the wheel are making contact. And when you screw down the three screws, ensure the thin metal disk is center in all three holes and is riding on the collar. Start screwing down the screws a turn at a time, alternating between them, push down the on the metal cup as you go to ensure the horn / relay is working. It will snug up as design if every thing is lined up correctly. The main issue I've had is over tightening the screws which will not allow the thin metal disk to spring back after it is pushed in with horn button. When that happens, you have to start over as described. That how I figured it out, hope it helps. D/