Horn button

Hi, my horn works perfectly. I short the wire that comes up through the steering column to ground (first pic) and the horn blasts (or I simply hear the relay activate, if I don't yet have air pressure). I found a rubber cover and metal shroud in a kit (second pic) that I can't get to work. Am I missing parts, or for a different wheel? I doubt wheel (picture 3) is original to truck. Thanks!

That brass cup is supposed to 'short' the top connector to earth. (On that steering wheel nut). The spring holds the top 'connector', AND the brass cup OFF the nut.
Try cleaning it (the nut) thoroughly to make a good contact..

Concur. I had to sand that nut down with emery cloth to get the button working, I also coated it with dielectric grease to try to slow down the return of the rust.

Thanks. I cleaned everything and verified that the horn works when the center wire shorts to the wheel nut, before I made the post. But the cup (aluminum colored in picture 2) does not contact the wire when centered. The center hole is too big. Maybe this kit is for another application, or I am missing a part. I have never seen the complete set-up.

These links may help you.

http://trucks25ton.tpub.com/TM-9-2320-209-20-3-1/TM-9-2320-209-20-3-10629.htm

Horn Repair and Steering Wheel Replacement


old style horn button kit;
http://www.eriksmilitarysurplus.com/hoburekitfor.html

new style horn button kit:
http://www.eriksmilitarysurplus.com/hobuswkitfor.html

Thanks, everyone.