Not enough power??
 

Been having issues with my horn. Sometimes it works, sometimes it doesn't, sometimes it "sorta" works with the "sick cow" syndrome. Through a little testing yesterday I discovered that, it works best with the car not running. With the car running and the cowl lights on, the Ammeter draws 7 amps and dos to 16 amps when the horn button is pushed but the horn won't function. If I rev up the engine, the horn will start to function in the slow sick cow range. With the car idling and the cowl light s of it will sometimes moan. Seems like it just isn't getting enough juice when the car is running unless the engine is reved up and even then not always enough for full function. Does this mean that I need to adjust my generator??. The horn is an aftermarket 6V horn with no adjustment screw. If I run wires directly to the battery it works great. PS. I removed the horn button and checked it out and all looks good in there.

Re: Not enough power??
 

Have to you tried adjusting the horn?

Re: Not enough power??
 

I have similar problems with my aftermarket model A horns . If the engine isn't running fast enough for the generator to begin charging , the horn sounds like a sick cow . Some of my model A's are running twelve volts . The horn is loud and strong whether on 6 or 12 volts. when the generator is charging at high enough rate ..

Re: Not enough power??
 

My horn was intermittent. I removed the light switch at the base of the steering column and wiped oil off of the round contact area between the switch and horn rod. It work fine now.

Re: Not enough power??
 

I had the sick cow syndrome until I oiled the horn properly

Re: Not enough power??
 

Good point all. Those danged old inventions need attention in all areas.

Re: Not enough power??
 

Its very simple to add a horn relay.

Re: Not enough power??
 

Now THERE's a good idea.

Re: Not enough power??
 

I have some 6v relays. Anyone have a wiring diagram to use on 6v pos ground horn?

Re: Not enough power??
 

Here ya go -

Attachment 438824

Re: Not enough power??
 

Thanks. Since my relays have 5 terminals, all I need to do is figure out which ones to use.

Re: Not enough power??
 

Here's another one I had found. https://www.pinterest.ca/pin/7070652...c_v2=1a5PxJ8EC

Re: Not enough power??
 

How simple? Maybe I’m simple. Free horn relay up for grabs!

Re: Not enough power??
 

The horns were series wound motors much like a starter motor only much smaller since the torque requirements aren't near as much. These type of motors draw a lot of current. When the horn is only powered off the battery, it can draw more current that when the generator is carrying the load.

Proper maintenance of the horn and all related electrical connections will definitely help with reliable function but sometimes the motors develop armature, brush, bearing, or field problems that require repairs.

I have no doubt that they functioned well when they came off the assembly line but that was 90+ years ago.

Re: Not enough power??
 

So that diagram wants the horn to be grounded separately from the grd that comes from the horn switch and energizes the relay. That’s hard to do without a separate wire, unless your headlight bar has a good grd. Most don’t. Then, in order to bypass the original “hot” wire that goes through the amp meter and light switch ect, a new hot wire must come from the starter or battery. It seems simpler to just repair the weak connections that are causing the problem.

Re: Not enough power??
 

Not in my particular case. I've spent several hours checking every connection in the system. Had the horn button apart, the light switch, the connectors by the rad shell (several times and changed them twice) and had the horn apart twice to check for connections and make sure that it spins freely and is properly lubed all to no avail. Horn will not work at an idle but will start to work as I rev up the engine but even at good RPM (2000ish) it works but is slow to each proper speed.
It works great when wired directly to the battery. 30 minutes to wire in a $20 relay is time and money well spent. Perhaps not for other cars but for this car it's a no brainer.

Re: Not enough power??
 

I have never seen a wiring diagram for 6v pos ground 5 terminal relay anyway.

Re: Not enough power??
 

Relays dont care about polarity or voltage,what a relay does is allow you to control a high amperage circuit with a milliamp control,basically you don't run the horns load through the button.Modern electrical systems use relays to reduce switch loads and provide full load to the component .Its no where near period correct,but its a better way to skin the cat.I used relays and modern fuses to protect all my circuits..It makes troubleshooting easier and my harness wont burn if something goes wrong..

https://i.imgur.com/cfcOdPm.jpg?1

Re: Not enough power??
 

Just run a heavier gauge wire straight from the battery to the horn. You may need an in line fuse on the wire to protect it. Ford connected it direct to the generator cut out but it would likely get less resistance in the line if it was connected direct to the battery. It should run OK with a 16 gauge wire but it wouldn't hurt to use a larger gauge. You can try it with a heavy gauge jumper set up and see if it turns better.

I wonder about the quality of some of these model A wiring harnesses some times. When the car is running, there may be a loose wire in the terminal box or under the instrument panel causing more of a resistance load than just the ignition system. High resistance with the ground path is just as bad. It doesn't take much for the system to get overloaded with only a 12 to 15-amp generator pulling the load.

Re: Not enough power??
 

The ones that I've used had the wire ends crimped only . I soldered the wire end connections and have had no problem .