The Stovebolt Site Forums The Shop Area The Electrical Bay 1958 Horn Rebuild

Has anyone attempted to repair one?
I have this one apart and cleaned with deoxit + inspected the windings and contacts.
The thin metal spacer between is deteriated and wondered if that may be the cause of why it
does not work?
Aside from that it looks good.

My original horn didn't work, disassembled as you have, windings are not open, contacts are clean, I couldn't make sense of it. I installed a couple of Craigslist horns to make mine road legal.

I rebuilt a similar one last week. There were a bunch of little things that I fixed, but the two that caused it to not work were:

1. Burned contacts: I took the "switch" stack apart and had to sand the contacts down quite a bit to get to clean material. It looked like they had gotten a little rusty, then tried to weld shut shut when someone held the button too long. They were badly scorched and pitted.

2. Cracked solder joints: The switch is soldered to the coil wires and with time and vibration one side was badly cracked and the other side was not looking good. I resoldered all of the connections.

With those two fixes, I was able to measure the resistance through it. Then I had to adjust the tone nut (which I am sure has a real name) to get it to cycle properly with the slightly different switch thickness.

By inspection of your pictures, I would recommend looking at the spacing on the switch. When you push the button, the coil activates and pulls the diaphram "up", which opens the switch, cutting off power, letting the diaphram relax and the switch to close again.

The tone can be controlled somewhat by the switch preload and depth. It looks like this one uses a collar on the diaphram rather than the nut that a lot did.

Does the diaphram post move smoothly in/out of the coil?

Yes it does. It was rusted. I sand papered and cleaned. I just tried to test it. still no noise. I will take it
back apart and sand the contact.
I am just running a wire to + on a battery and trying to ground the horn on the frame using the
mounting bracket. Will this work?

If I were to check junkyards, what years and models would have this type of horn?
I think it says Type S

As far as overlapping vehicles, I don't know.

Wiring it directly to the battery should be fine.

I suspect either a dirty contact or the switch is out of adjustment. You should be able to measure across the switch with your multimeter.

Guys, just a note that this conversation best belongs in the Electrical Bayso it’s been moved there for more discussion. 👍

Tri-Five Chevrolet cars have similar horns. I was looking for more details on horn rebuilds and came across this post. I was successful to get noise out of my low-tone horn by the following steps:
- drill out all the rivets
- this will allow all components to separate
- Take pictures of how each piece in the assembly comes apart
- I used some very fine media (700 grit?) in my HF sandblaster to clean up all pieces.
- my thin metal piece (reed?) looked to be in better shape than yours
- I had a local gasket shop make a gasket to replace the paper one that had been in place since it was new!!! try to match the thickness (.035"?) of the +60 year old one
- look at the face surface of the cast piece. I think this should be flat, check with a metal ruler or straight edge. I had to take a sanding block to level out the high spots, this takes time to accomplish
- Use your pictures to re-assemble. I elected to use 10-32 allen-head screws, washers and nuts because I could not find the correct rivets. Tighten them in a star pattern.
- It makes sense to me that this reed is in a correct state of tension, not sure what that is or how to measure it!!!
- Spray assembly with self-etching primer, let dry and then spray with correct shade of black to match your under-the-hood parts.
I am not sure this is the correct way to do this, that's why I am looking for validation or someone else's method and suggestions.
i think we can benefit by posting a picture so we all know what to use a multi-meter to check out continuity and voltage readings.
There are some details on horns in the 1958 Trck shop manual.

This horn has not been totally disassembled, the rivets are still in place to hold the reed to the cast spiral section.

I'll post another pdf after I take apart the other horn to show more details on it. Please feel free to download it and attach check point detials.