Over charging causin g bulbs to blow?

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colonelpowers
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Over charging causin g bulbs to blow?

Post by colonelpowers » Fri Sep 23, 2022 10:33 am

Hello Everyone,

I was driving my 27 tudor the other day when apparently the cutout started acting up. It pegged out the amp gauge and stayed there for about 20 mins. until I arrived at my destination. I stayed all day and then returned home late that night. In the dark I couldn't see the amp gauge but I could feel that it was hot. The headlights were good and bright. The next day I was checking things out and saw one of the plastic amp gauge nuts melted and laying in the floor. The old girl started right up and the amp gauge was reading a normal charge. I flipped on the headlight switch to see how the gauge reacted and no change. Checked lights and none were burning. Removed tail light and it was burned out. Looking through headlight lenses the bulbs look dark. Anyone else experienced this before. All the lights were working and bright when I turned the car off that night.

On a side note. I cannot get the headlight rings off. They have relatively easily come off in the past but I can't get them to budge now. Any tricks you can think of?

Thanks and God Bless,

Joshua A Powers


TXGOAT2
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Re: Over charging causin g bulbs to blow?

Post by TXGOAT2 » Fri Sep 23, 2022 10:41 am

That sounds like your generator system was overcharging by a lot. I don't believe a regular cutout could cause that. A bad cutout can damage the generator, but it should not affect the rest of the system. A regulator style cutout might cause overcharging if it failed. Burned out bulbs and darkened bulbs indicate overvoltage. A problem with the battery or battery connections could cause it. An accessory master switch that was opened inadvertently while driving might cause it. A loose third brush adjustment might cause it. Anything that could cause the battery to become disconnected from the rest of the system could cause it. I would not use plastic nuts on any electrical connection. I would not depend on the amp gauge. It may be damaged and giving a false reading. I supsect the high reading was accurate, and that the amp gauge was damaged by too much current. Your generator may also have damage. You need to determine exactly what caused the runaway charging and correct it. After that, I'd replace all bulbs and the amp gauge and check the generator and battery for evidence of damage. Check all electrical connections for cleanliness and tightness. If you have battery disconnect switch, NEVER open it when the car is running, and be sure it is in good condition and that all connections are clean and tight with no evidence of overheating.

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TRDxB2
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Re: Over charging causin g bulbs to blow?

Post by TRDxB2 » Fri Sep 23, 2022 10:57 am

colonelpowers wrote:
Fri Sep 23, 2022 10:33 am
Hello Everyone,

I was driving my 27 tudor the other day when apparently the cutout started acting up. It pegged out the amp gauge and stayed there for about 20 mins. until I arrived at my destination. I stayed all day and then returned home late that night. In the dark I couldn't see the amp gauge but I could feel that it was hot. The headlights were good and bright. The next day I was checking things out and saw one of the plastic amp gauge nuts melted and laying in the floor. The old girl started right up and the amp gauge was reading a normal charge. I flipped on the headlight switch to see how the gauge reacted and no change. Checked lights and none were burning. Removed tail light and it was burned out. Looking through headlight lenses the bulbs look dark. Anyone else experienced this before. All the lights were working and bright when I turned the car off that night.

On a side note. I cannot get the headlight rings off. They have relatively easily come off in the past but I can't get them to budge now. Any tricks you can think of?

Thanks and God Bless,

Joshua A Powers
A cut-out does not regulate charging its a simple on/off switch to disconnect the generator when the engine is shut off. It sounds more like you have a short somewhere. If you pegged the amp gauge it would mean that something was wrong with the generator and with the headlights not working things are not back to normal.
Rather then speculate now to the cause, it would Would help to understand more about your electrics. Do you have a fuse to the battery? 6 volts I assume. Were you driving on MAG or BAT? Had you done any work on the wiring recently? Is the ignition switch an original or repro? Same question for the Stater switch original or repro? How did you decided determine that the cut out was acting up ? Is the cut-out a solenoid or diode and do you know where you got it?

To remove the headlight rims, first go around the rim kneading it against the bucket so you fell the spring compressing. Then compress the rim and turn it counter clockwise. Sometimes 4 hands work better,.
The past is a great place and I don't want to erase it or to regret it, but I don't want to be its prisoner either.
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Norman Kling
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Re: Over charging causin g bulbs to blow?

Post by Norman Kling » Fri Sep 23, 2022 11:19 am

The cause of this would be an open connection between the switch and the battery. The generator is still charging, but with a stock system, the battery itself acts as a voltage regulator. The amps which would have gone to the battery are instead, going to whatever is turned on. Sometimes this situation even fries the ammeter. Usual causes. A blown fuse between the starter switch end of battery cable to the ammeter. If not a fuse in the circuit, a bad connection or open connection between the connection at the starter cable and the terminal block, or between the terminal block and the switch panel. Or it could be the battery cable either the positive cable from battery to starter or the ground cable from battery to chassis. First thing to check would be corrosion at the battery posts and the clamps at the end of the cables. Then the connection of the ground strap between battery and chassis. Sometimes the chassis becomes corroded at that point and the connection is not good. Or on some battery cables, the ends are pressed into the cable and not soldered, which connection becomes loose or corroded.

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Rich Eagle
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Re: Over charging causin g bulbs to blow?

Post by Rich Eagle » Fri Sep 23, 2022 11:23 am

Years ago, my Model A blew the bulbs out frequently and I believed it was when the path from the generator to the battery was broken and full current went through the lights. Both headlights often blew at once.
It might be the problem.
Rich
(Typing while Norman posted.)
When did I do that?

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TRDxB2
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Re: Over charging causin g bulbs to blow?

Post by TRDxB2 » Fri Sep 23, 2022 11:35 am

Here is a wiring diagram for reference to the terms used to identify the wiring
Attachments
26-27 color coded diagram.jpg
The past is a great place and I don't want to erase it or to regret it, but I don't want to be its prisoner either.
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speedytinc
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Re: Over charging causin g bulbs to blow?

Post by speedytinc » Fri Sep 23, 2022 11:36 am

I am no electrical genus, so keep that in mind.
For the generator to go wild, the battery connection must be broke. Since it effected the lights, its down wind from the cutout, not the cutout failing
Thinking a disconnection, temporary like dirty cable contact.

I had a similar experience on an old harley. Running a gel cell down the freeway. Heard a pop & the ammeter went high charge, burned out all the light bulbs. Lucky to not burn out the coil. The motor ran crappy. I pulled over & it died. Upon inspection, I discovered the battery had blown up inside the carrier. I believe the battery connection opened internally, & sparked.

The ammeter is the only gauge Ford thought important. Monitor closely as you drive. Heed its warnings. Watch for a lack of charge. That usually means a cutout failure & you need to immediately ground out your generator to save it. Seeing the ammeter peg high would first have me scratching my head for a half second(very unusual) but still puts the alarm flag up to shut her down fast.

(Slower typer than the 3 above me.)


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Re: Over charging causin g bulbs to blow?

Post by upman » Fri Sep 23, 2022 12:15 pm

had the same type of problem once, found that the ampmeter was bad, changed it out and no more problems


Jerry VanOoteghem
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Re: Over charging causin g bulbs to blow?

Post by Jerry VanOoteghem » Fri Sep 23, 2022 4:09 pm

upman wrote:
Fri Sep 23, 2022 12:15 pm
had the same type of problem once, found that the ampmeter was bad, changed it out and no more problems
Same here! One of the ammeter terminals came loose and shorted to ground. Blew out every light bulb in the car, (every one that was on when the short occurred).


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Re: Over charging causin g bulbs to blow?

Post by TXGOAT2 » Fri Sep 23, 2022 9:12 pm

An "open" ammeter would have the same effect as an inoperative cutout. I suppose a shorted to ground ammeter would cause the cutout to "chatter" until it failed, whereupon the generator would run away. System voltage would probably fluctuate wildly until the cutout failed, which would likely trash any bulbs that were lit.

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