| silverchief | -- 06-14-2012 @ 5:03 PM |
|
On my 46, I think I may have fried my horn relay. They have worked only intermitently in the past using the horn ring. Work fine with direct power from battery. Was checking with horn ring and heard only clicking. Opened hood to check connections and smoke and heat was coming from relay. Took me couple of minutes to disconnect power. How do I test relay using a voltmeter - and should I replace entire wire from button down - suspecting a short. Thanks.
|
|
| supereal | -- 06-14-2012 @ 6:28 PM |
|
There are three terminals on the horn relay. One receives battery power. One connects to the horn(s), and the final post connects to the wire from the horn button or ring. If they are not marked, remove the housing from the relay and trace the circuit. When a horn relay burns up, it is usually because a horn is shorted, or there is a ground in the wire to the relay from the steering wheel that keeps the relay pulled. In either case, the relay is pulled until the smoke rolls. A relay is used because horns draw lots of current. The relay itself is rarely the problem unless the contacts have locked. This message was edited by supereal on 6-15-12 @ 6:09 AM
|
|
| fla48 | -- 06-14-2012 @ 7:28 PM |
|
When my horn relay only clicked, I found a short between the relay and the horns. One of the wire connectors was not completely plugged in and was shorting out against the radiator support. I would look for a short and then install a new relay.
|
|
| silverchief | -- 06-16-2012 @ 9:32 AM |
|
Thanks. Got a new relay. Old one says made in USA New one has no indication whatsoever as to manufacture. My dad used to say "Never buy anything a man is ashamed to put his name on." so I am not expecting much. Do I have to pull the steering wheel to install my new horn wire?
|
|
| supereal | -- 06-16-2012 @ 10:39 AM |
|
No, you can replace the wire from the horn ring to the bottom of the column by first turning the ring counter-clockwise to release it, then disconnect the wire from the ring where it is held by a screw. Disconnect the other end of the wire from the connector and attach a "pull" string to the wire. We use a strong nylon fishing line for that purpose. Pull the wire up throungh the center of the shaft until the pull string is available. Tie the string to the new wire and use the string to feed the wire until it reaches the bottom of the shaft and comes out of the box. This usually requires someone to help to feed the wire as it is pulled. The wire is available from C&G for about 5 bucks (11A-14308), if you need it. While you have the horn ring off, check the condition of the sponge rubber "donut" to see if it needs to be replaced. they are often hard, making using the horn intermittent. The part number is 11A-3672.
|
|
| silverchief | -- 06-16-2012 @ 11:25 AM |
|
Supereal - I need some more help. The horn wire sold me by local old Ford parts guy is a slightly smaller gauge than what is in the car, and has a plastic knob with metal insert on the end. Don't think it is for my car so ordered one from C&G today. Rubber donut is not great, but OK I don't really understand how the horn ring works. It has a metal plate inside the donut, with 4 screws, one obviously for hookup to wire. Other 3 have an insultating fiber washer between head of screw and the plate. Why is that? Should they be tightened down securly? Is ground made when metal ring attached to the horn ring touches the metal plate on the steering colum? I'm trying out figure where short occurred that caused relay to smoke. I pulled relay apart and points are junk but no obvious signs of extreme heat. 3 wires to relay show no bare spots or sign of excess heat. I hate to hook up new relay and horn wire to have same thing happen again. Pls advise. This message was edited by silverchief on 6-16-12 @ 11:27 AM
|
|
| supereal | -- 06-16-2012 @ 2:15 PM |
|
The stock horn wire has built-in resistance. That prevents getting a shock when you use the horn ring. The relay coil works like an ignition coil, and produces a voltage spike as the coil is released. The correct wire for your '46 is a straight wire with a bullet connector on one end and a loop terminal on the other. See my previous post for the part number. The wire need not be heavy, as it is used only as a ground for the horn relay coil, and doesn't carry much current. The rubber donut serves two purposes: it insulates the horn ring, and acts as a spring to keep the ring away from ground until the ring is pushed. When the ring is pushed, it compresses the rubber and the ring "finds" ground at the steering wheel hub. That is why we usually recommend replacing the rubber ring. It is less than 5 bucks, and could prevent cooking another relay.
|
|
| silverchief | -- 06-16-2012 @ 5:03 PM |
|
Thanks Supereal - will order a new donut first thing Monday. My horns are the original trumpets. I removed them and touched up the points with a point file. Axious to get it all back together.
|
|
| Old Henry | -- 06-16-2012 @ 11:14 PM |
|
Super, that's good to know about the horn wire resistance. I've always wondered why I sometimes get a little shock where my left arm is resting on the window sill when I honk the horn. Now I know. I know I don't have the original wire. Now I'll get the right wire and maybe be free of that occassional "sizzle." Old Henry (The older I get, the better old looks.)
|
|
| supereal | -- 06-17-2012 @ 6:52 AM |
|
OH: You can insert a resistor in series with the wire from the button to the relay, and not go to the trouble of replacing the wire, itself. I don't recall the resistance we have used, at this moment, so I'll have check to see. The size of the resistor isn't critical, as long as it doesn't block the access to ground from the button or ring.
|
|
| EFV-8 Club Forum : | https://www.earlyfordv8.org/forum |
| Topic: | https://www.earlyfordv8.org/forum/viewmessages.cfm?Forum=18&Topic=4797 |