Weird electrical problem?

dlfrisch said:
Your ampere meter is part of the complete electrical wire loop from the charging unit to the battery. It has no ohm resistance. Take one wire off of the amp meter and check for continuity across the unit. Should have no resistance.
Dave
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RIGHT ON, Dlfrisch, those slotted nuts that hold the posts in the ammeter are often overlooked! Tom W. made a nifty tool to tighten them. Some ammeters can be taken apart, & you can study the innards. It's FUN to take the "mystery":confused: out of them, & oil the needle shaft, that sometimes sticks.
Bill W.
 
I may have missed someone else asking this question and if I I'm sorry but, when you removed the ammeter from the circuit I assume you connected the two wires together?

I don't know how your car is wired, on a stock model A having that open wouldn't let the car run but it would crank. The wires must be shorted together as the ammeter is in series with the circuit. If they are just hanging there not connected you disconnected power from everything on the other side of the meter.
 
Hmmm, that's an interesting point, as I thought the ammeter was simply in parallel across that circuit, to monitor it... so my expectation would have been that to remove it from the picture would not have any effect on it. I guess I need to take another look at the Model A wiring diagram, when I get a chance.

And, to answer Mr. Tube's question, no, I did not connect the two wires together; I simply disconnected both wires from the ammeter, to totally remove it from the equation. (I did, however, put a VOM across the two wires (when the ammeter was still removed) and read close to 6-volts DC between them)...
 
When during all this did you disconnect the ammeter, before you posted your question?

Please hook it back up or at least connect the two wires together.

Then would you please look at the drawing that Willie posted with the wiring diagram and you will see how it fits into the whole cars electrical system.

I'm sorry if this is going to confuse you but there was a wiring change in 1929. Before that coil did not read on the ammeter.

Unless your car is for show, and you have a slant pole coil please use Willies drawing and wire the ammeter the way it shows on the drawing. Having the coil read on the ammeter will help future trouble shooting of the ignition system as you will see the opening and closing of the points when starting the car is all is good.

http://www.fordbarn.com/forum/showthread.php?t=97192
 
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All this was done before I started the post. Also, as mentioned earlier, my car has a Zipper FS Electronic Distributor system in it, so if I remember correctly, there were a couple of minor changes made in the way the wiring goes to/through the junction box, so its possible that the changes mentioned by Willie may not apply to my situation, because of this difference in wiring needed by the Zipper. I've been driving it in its current Zipper configuration for 3 years now without any problem, so this is all surprising to me. In any event, the ammeter IS hooked back up, since removing it from the picture a few days ago made no difference in the symptoms.

I am out-of-town at the moment, but am planning to spend some time on the car this coming week when I get back home, and I will re-trace all of the wiring from battery to starter to junction box, just to see if there's anything obvious. I will also remove the ammeter and connect its two wires to each other, to see if there is any change in the symptoms as presented.

My continued thanks to all for sharing their thoughts and input!
 
Re: Weird electrical problem - Problem Solved!

Well, I finally got to do some more research into my problem here, and ended-up getting it resolved!

While all connections between the battery, alternator and junction box were clean and tight, I started to think about the concept of having a high-resistance connection somewhere, especially since the lights only worked with the engine running. I then decided to take a look at the lighting switch (at the bottom of the steering column), since my steering box tends to slowly leak gear oil down into the switch unit. So, I removed the bale and pulled the switch out and opened it up. While it didn't seem flooded with oil, there was a bit of oily film inside, so I first wiped it all down and then sprayed it completely dry using a can of Contact Cleaner. I put it all back, but the lights and horn system continued to remain dead (unless the engine was running).

I then tried wiggling the wiring harness where it comes off of the BACK of the lighting switch, and suddenly the cowl lights came on (with the engine OFF). This was definitely progress! So, I proceeded to remove all of the wires one-by-one from the back of the lighting switch, and sprayed all of the spade-lug contacts with contact cleaner, to insure that no oily film was hindering good, clean contact where the wires meet the back of the switch.

Upon further testing, everything was once again back to normal... with all the lights, the horn, and even the ammeter reading properly! So, the problem appears to have been been a dirty/oily connection in the back of the headlight switch... and I now know what to look for if it ever happens again!

In closing, I hope my findings will be of use to anyone else who might run into the same symptoms... and I do thank all of those who shared their input into my situation!
 
Re: Weird electrical problem - Problem Solved!

Bobs29ModelA said:
Well, I finally got to do some more research into my problem here, and ended-up getting it resolved!

While all connections between the battery, alternator and junction box were clean and tight, I started to think about the concept of having a high-resistance connection somewhere, especially since the lights only worked with the engine running. I then decided to take a look at the lighting switch (at the bottom of the steering column), since my steering box tends to slowly leak gear oil down into the switch unit. So, I removed the bale and pulled the switch out and opened it up. While it didn't seem flooded with oil, there was a bit of oily film inside, so I first wiped it all down and then sprayed it completely dry using a can of Contact Cleaner. I put it all back, but the lights and horn system continued to remain dead (unless the engine was running).

I then tried wiggling the wiring harness where it comes off of the BACK of the lighting switch, and suddenly the cowl lights came on (with the engine OFF). This was definitely progress! So, I proceeded to remove all of the wires one-by-one from the back of the lighting switch, and sprayed all of the spade-lug contacts with contact cleaner, to insure that no oily film was hindering good, clean contact where the wires meet the back of the switch.

Upon further testing, everything was once again back to normal... with all the lights, the horn, and even the ammeter reading properly! So, the problem appears to have been been a dirty/oily connection in the back of the headlight switch... and I now know what to look for if it ever happens again!

In closing, I hope my findings will be of use to anyone else who might run into the same symptoms... and I do thank all of those who shared their input into my situation!
Click to expand...


This is from Bratton's catalog:
1930-31 one bulb: For horn headlights and tail light. Use one bulb set if you have cowl lights. This harness is made from the Ford print and includes the correct wire bullet ends for the wire to the headlights for a perfect fit. Best wiring available. Correct color coded wire. Wire ends are soldered to terminal disc. Yellow wire and blue wire with yellow tracer go to horn. Yellow wire inside loom to cut out. This can be used on 1928 cars if (# 16690) is replaced with a repro light switch body. The 1929 wires have the stop light wires NOT braided inside a loom, but two separate green wires.

I looked at an old Ford loom I have and the wires are soldered to the
terminals on the disc.

Bob
 
Thanks for sharing your solution! I have the same issues with lights and horn only working when engine is running so as soon as I have some time I will check the lighting switch!
(I will disconnect the battery this time, as last time I disconnected the light switch I blew all light bulbs...:()
 
Badaboom said:
Thanks for sharing your solution! I have the same issues with lights and horn only working when engine is running so as soon as I have some time I will check the lighting switch!
(I will disconnect the battery this time, as last time I disconnected the light switch I blew all light bulbs...:()
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How did you disconnect the light switch in such a way that it blew the bulbs?
If you disconnect the battery from an unregulated generator, then the voltage will shoot up and blow the bulbs.

Are you using a master disconnect switch? Are you using a fuse?
 
Tom,

I don't have a fuse and no master disconnect either (both are on the to do list, but I only got the car recently). So the system was under power when I disconnected the lightswitch (by accident). All bulbs except one signal light were blown...
 
I don't use a fuse nor master disconnect switch, but only asked to see if they were opened with the engine running, which might have cause the high voltage spike that blew the bulbs. By disconnecting the lights, did you mean you unscrewed the power feed wire at the cutout?
 
...but only asked to see if they were opened with the engine running, which might have cause the high voltage spike that blew the bulbs.
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Ok, now I understand what you mean. But if that were to happen the engine would stop running as well because there would be nog ignition right? I don't recall this happening.

With disconnecting the light switch I mean the switch on the bottom of the steering column. I accidentaly removed the bracket when working on the carburator and the switch fell off. After putting it back all bulbs were blown.
I understand your reluctance to this (probably) being the cause as a "shorting" during (dis)connecting of the switch would turn on the lights and not blow them but nothing else happened (as far as I know) between the time the lights were working and the time they weren't.
 
I think that the suggestions for (a) soldering all connections into the light switch, and (b) using dielectric grease on all contact points, are both the way to go, to either mitigate or eliminate any future problems... although I'm sure that having a steering box that doesn't leak gear oil into the light switch would also prove very helpful, too!
 
Suggest you check the contact point where the ground cable is bolted to the cross frame behind the battery. you need a clean, bright metal to metal contact and I have added a stainless steel star lock washer for added insurance. With the modified ignition and the alternator add an auxillary ground cable from the same anchor point behind the battery routed over to the transmission tower. The alternator does not work well if there is a loose electrical connection, especially a bad ground.
 
Bobs29ModelA said:
I think that the suggestions for (a) soldering all connections into the light switch, and (b) using dielectric grease on all contact points, are both the way to go, to either mitigate or eliminate any future problems... although I'm sure that having a steering box that doesn't leak gear oil into the light switch would also prove very helpful, too!
Click to expand...
Bob, I have some friends that think a "little" oil leak helps keep the headlight switch contacts from wearing, prevents corrosion, & makes the switch operate smoothly???:D Some others think 3 drops of oil will destroy their switch???:eek: Mine works perfectly, so, I'm NOT even going to look inside it! :confused:
Bill W.
 
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