I found an issue today, my 6v battery horn on my 23 touring sounds great when the car is not running. With the car running, it seems to only sound about a 1/4 of what it does when not running. After pushing the button a few times, the car starts missing and acts like it running out of gas and quits, no matter if I retard the distributor or not and any amount of gas. I find the fuse has blown, I only had a 20 amp fuse installed. Then after replacing the fuse with a 25amp, car will not start, the points are burned. So I changed the points along with a new condenser, at this point in time, I'm gun shy of pushing the horn button while the car is running, this is the second set of points that burned up.
Should I try a fuse in the feed to the distributor, so it blows prior to burning the points. I would of thought the condenser, would handle that issue, maybe I had a bad condenser?
This is the way I purchased the car in September 2017, I'm new to Model T's and currently I'm in learning mode, enjoying the challenges, but much rather enjoy some long term successes.
I've been working on the car almost daily a few hours here and there, fixed a LOT ok a TON Of little things that have been neglected by previous owners. Still have several open issues to address, the more I address and fix, the more I find needing attention.
Your T has been altered and modified. Distributors and fuses were never part of the original system so having them incorporated can be troublesome.
Folks who alter, modify and circumvent the OE ignition systems will chime in to help you out...
Let me add, it's negative ground, has a starter and generator. Distributor, from my research finding points, condenser, cap and rotor, is from a 1969 VW. Napa, is out of points and getting anymore, will cost me more for shipping then the cost of the points. I have one more set, I can get a condenser, have extra rotors and caps. I'm building another engine with my son, plan on making that setup back to original. That should happen next winter or early 2019, have lots of parts to round up to accomplish that task..
You may have to start from scratch and check every component of the altered system. This could prove to be difficult as there is no true "blue print" to follow .
You're going to have to rely on all of the "experts" opinions.
Bad condenser will burn up points. Most modern made condensers for VW's are absolute garbage. Search any VW forum and you will see what I mean. Im betting that is at least part of your problem.
I would NOT indiscriminately use larger fuses. Find out what size wire you have and fuse accordingly. The fuse is there to protect the wiring from overheating and catching on fire. If a fuse is sized properly, and it blows, there's a problem. A larger fuse isn't the solution.
The ignition would be wired to the battery terminal for hot on the switch as normal. You would be just swapping the wire to the coil in place of the wire that normally would go to the coil box. Where is the horn wired to? Where is the fuse installed?
This is the stock wiring for your car. I believe that with a disturbutor wire XW goes to the single coil, a 16 gauge wire goes from the coil to the points, and a plug-type wire goes from the end of the coil to the cap. I think everything else should conform to the diagram. Of course you want to check all connections to be sure they're clean and tight, and all wiring to be sure there are no superfluous grounds. I am an electrical dummy, so others may have corrections to my comment.
Sounds like a lot of things going on!
What kind of horn do you have? Is it a stock T horn, or something like a Klaxon? Klaxon horns take more current to operate.
Hitting the horn button and having it kill the engine is a sign of a problem with your electrical system. Honking the horn puts a lot of load on your electrical system, and if it has a poor connection somewhere, it will cause a voltage drop that will rob the needed voltage from the electrical system.
Yes, burned up points are a sign of a bad condenser. I would replace both. I would also say that you should possibly replace your coil... if your coil has some shorted windings (especially on the primary), it can still spark, but will draw too much current. That will also burn up points. Dwell that's really off can also cause excessive current draw.
I would say that this scenario is most likely. You said your horn sounds fine if the car is off. If your ignition system is drawing too much current when your car is running, then you honk your horn (another big current draw), it blows your fuse. That, coupled with a poor connection in your electrical system, is my official diagnosis!
Steve, I have that diagram by Ron Patterson, and followed that diagram when I wired in my headlights. I didn't verify all other wires were 100% correct at that time. I will double check all the wiring against the diagram to ensure they all match. Thanks for your help, picture and suggestion.
Hal, thanks for your concern, the original diagram called for a 25 amp fuse and I had only a 20 and 30 amp available, the fuse holder itself came with a 30 amp, so I used the 20 amp. I wouldn't install a larger fuse then the wire or diagram called for, I was just stating I used a 20 amp, maybe it was too small for this circuit was my thought.
Thanks everyone for your comments and suggestions
I redid the wiring to match the diagram 100%, since I have no mag and terminal one is missing the screw insides, I moved one to number 2 and wired the rest accordingly. I tested the wiring, everything seems ok, the horn was nice and loud. Started the car, pushed the horn button, seems ok at idle, when I give her more gas, horn is much softer. Occasionally the amp meter jumps to heavy discharge, but not blowing the fuse. My guess, since the points are not burning up, the condenser is working correctly, and the 25 amp fuse is big enough to handle this discharge when pressing the horn button. So I jumped the horn directly from the terminal block, it's louder then the horn button, but not by much, my guess is there is something wrong with the horn when the car is under a load? running on Bat only, can turn the lights on and no difference in the horns performance. Maybe you're only suppose to use the horn when at a red light and the person in front of you is sleeping?
I unplugged the generator, started the car, horn works great at idle, giving it more spark and gas, still can hear it about twice as loud as when the generator is hooked up?
I double checked the wiring, it's correct, correct size wires, and tight connections. I found when I hooked the generator back up, and ran the car, when running almost full throttle, the horn seems to work the first time you push the button, the gets softer each push of the button, till you can almost not hear it at all.
Could it be the horn is going out or not making good connection when running with more gas?
Don't run the car with the generator disconnected. Running the generator unloaded will make it burn up in pretty short order. If you need to disconnect it, run a jumper from the generator terminal to ground. That will load the generator and keep it from self destructing.
No, something is definitely wrong. The horn should get louder when the car is running and the generator is putting out. This is a real head scratcher!
It seems like somehow, your generator is un-generating. I think that that is unlikely and something else is wrong.
Does your ammeter show a charge when you rev the motor up?
What kind of horn do you have? Is it a stock T horn, or a Klaxon?
Hal: thanks for the information, wasn't aware of running without a load would cause issues..
Cameron: I have no idea what horn I have, I cannot find any markings on it, so I attached a picture.
That's a normal T 6vold DC horn. But that skinny plastic coated wire to the (+) terminal isn't doing any justice to passing current. Get correct gage wire there. And check the horn mounts to the block, you need good ground too.
Dan, the red wire goes from X -> W, it appears to be 14 gauge, I thought that wire was ok at 16 ? Unless I'm reading the diagram incorrectly. I will change that wire to 12 gauge as your recommending
I suspect that the generator may be an innocent red herring, having nothing to do with the erratic horn behavior beyond coincidence. You may be having separate, unrelated electrical glitches. I agree with Dan about checking the horn for good ground. I think he's referring to the black horn wire, not the red X-W. But also find out if the horn button is making good contact consistently. Intermittent contact there could be the source of your horn's erratic function.
Steve, maybe I misunderstood Dan, I thought he was referring to the wire from the switch to the coil wire. What size wire should go to the horn button and then to the horn, I think the currently wiring is 16 gauge. There is no ground wire on the horn, it appears it is grounded by connection to the head?
I'm headed over to a friends place to help him out and hopefully remember to pick up a horn, while I'm there, he has several I can use to test with. I will try to test one of those horns out with my car this afternoon if possible. Hopefully that will rule out the horn or identify it's actually the horn that is the problem, or as suggested a bad ground,
Thanks for your help and suggestions
If the horn wires are 16 gauge that should be good enough. Yes, the horn ground is through its mounting to the engine. Be sure you have good metal-to-metal contact there, and be sure the horn button is working reliably.
First of all, why not mount your horn correctly?
Second, Model T's used no fuses anywhere. It appears to me you have a wiring problem. New wiring will probably correct your problem.
Looks as though the distributor ignition coil is in the way of where it should be mounted.