VCCA Home Forums TECHNICAL - GENERAL Electrical - 6 volt Dual Trumpet horn wiring.

I have a set of trumpet horns for my 1934 Master. When I hook one horn up it works fine. When I hooked up the second horn, it started smoking. These are horns with two terminals. After I hooked up the first horn, I tested the wires for the second horn. They both showed 6 volts. Without any horns hooked up, they test normally (one hot wire and one ground wire). I am not sure what's up. What is the best way to test the continuity of the horn motors?

Pictures? Not sure what horns you're referring to. My accessory horns have one hot wire and ground through the case.

My horn motors are two wire k-26 Delco. I salvaged them from other old used horns. I'm in the process of trying again. I could not yet find a short in either horn.

Here are some ideas to consider.

Have you tried each horn individually? That might give you a clue to help troubleshoot.

Should you be using a relay to properly handle the large amps that these horns draw? It could be that there is so much resistance in the circuit that things do not work properly.

Do you have the horns wired in parallel or series? Unless they are different than I expect they should be in parallel. Otherwise the first horn gets all the power. The second one probably gets enough power for the points to close and not vibrate. That overheats the coil.

I have never continuity tested a horn without having access the the points to manually open and close them. I do not know if the points are closed in the “off” position or open. These horns are simply an amplified vibrating coil. They work just like a coil in a regulator. They make and break their own circuit when power is applied.

Thanks Rusty. I have a new wiring harness from Y and Z. The harness tested fine. I noticed on the horn that I have continuity between the terminals. This may be a problem, as they will both be hot when one of the terminals is connected. I may have to rewire horn so that one terminal will go to ground. I have a few horn motors to play with.

I solved the problem. Horns for a dual horn set up are wired differently inside than single horns. I was able to convert them (with a little difficulty) to work. It is possible, but the horn needs to be dismantled. The dual horn has an extra metal bit which is vital to the rewire. So.....all K-26 Delco Remy horn motors were not created equal.

Dual horns require a horn relay due to heavy current draw.

Thanks Gene. Does anyone know where the relay is located?

On the accessory horns for my '37 the relay is mounted on the bracket that supports the 2 horns.

Same on my 35 Master and 36-37-38 and 39"s but 34 Masters don't have this bracket. I'de be interested to know where it's mounted on a 34 also.

the 1934 dual horn relay was mounted on the left side inner fender under the hood across from the generator.A 12 gauge wire should be used from the starter switch to the battery termial on the relay. At least a 14 Ga. to the horns. Most relays have the three terminals stamped with battery, horns etc.

Thanks Gene, Great Info.