discharge while running lights

[todd3131]

When I run my A with the lights off it charges 15 amps when I turn my lights on it discharges down to 6 amps. I have looked at everything I can is this normal or do you have suggestions? I thought it might be a short but I can't find one.
Todd3131

[1930artdeco]

That is about right. it should charge at about 8-10 amps and then discharge at about 2 amps with head lights on. You might get a bit more discharge if you have the high beams on. It will come down to adjusting the generator correctly. If you have an Alt. I have no idea.

Mike

[H. L. Chauvin]

If a short, first look at a wiring diagram.

1. The headlight switch at the base of the steering wheel gets volts via the the wire connected to the cut out on the generator.

2. From this switch controlled on the steering wheel, in each one of (4) positions, volts to lights are as follows:

a. Bright headlights + taillights.
b. Dim headlights + tail lights.
c. Parking lights or cowl lights + tail lights.
d. Off -- where no discharge occurs; hence, no problem.
(Brake pedal engages brake light -- does discharge occur also with brake lights?)

3. From the above (5) paths of volts, how many of the (5) can register a discharge?

4. The light switch positions which indicate a discharge should give you a clue as to which light circuits to check for shorts.

5. Then you can disconnect one light at a time to see which particular one(s) are shorting out & get back with a report on same.

Hope this helps in your search.

[Patrick L.]

Are you saying that with the lights on, it still shows a positive 6 amp charge ? Or, is it showing a 6 amp discharge ? I don't quite understand the post.
If it is showing a 6 amp charge with lights on, then I'd think your fine. I would however reduce the overall charge. I feel 15 amps is kinda high.
If it is showing a discharge, then there is something wrong. The headlight connectors can be a real PITA. A grounded wire/connection is fairly common with these. Many fellas just bypass them. So, disconnecting one light at a time could lead you to the problem.
This is assuming your running 6v and generator.

[marc hildebrant]

Todd,

If you are using the original generator setup, then the amount of power (Voltage times Current) from the generator is mostly constant. So, with the lights off, the power is more than you need and the battery shows a charge. With the lights on, the power from the generator is not enough and the battery shows a discharge.

Marc

[Tom Wesenberg]

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15 amps charge is too much and will cook the battery.

If you are dropping to -6 amps with the lights on, then they are pretty high draw bulbs. Are they sealed beam?

My lights only draw about 10 amps.

[todd3131]

It has a 21 point swing from positive to 6 negative when the lights are on I think I will go through H.L."s list and see what I get next week when I can get a chance to work on it. I do know that when the battery is not at a full charge and running with the lights on it definitely does not run as well.

[Patrick L.]

So, we still don't know what you have. 6v or 12v. Generator or alternator.
I'll assume [ we know what that means] its 6v generator. I'd recommend starting with adjusting the moveable third brush to reduce the charge to 10-12 amps if a lot of night driving is done or 4-6 amps if not. Then look for the big draw, most likely headlight connections.
Once it fixed, I'd recommend one of Tom W's EVR's.
I'd also recommend a good repair manual with a wiring diagram.

[jmeckel]

One other point here, what kind of bulbs do you have? If you are running halogens they draw a lot more than the original style bulbs.

[todd3131]

Originally Posted by Patrick L.

So, we still don't know what you have. 6v or 12v. Generator or alternator.
I'll assume [ we know what that means] its 6v generator. I'd recommend starting with adjusting the moveable third brush to reduce the charge to 10-12 amps if a lot of night driving is done or 4-6 amps if not. Then look for the big draw, most likely headlight connections.
Once it fixed, I'd recommend one of Tom W's EVR's.
I'd also recommend a good repair manual with a wiring diagram.

The car is bone stock and my problem isn't the charging rate it is the amp draw from the light the charging rate is easily adjustable my question is the amp draw from the lights and previous posts have suggested it is too high having stock bulbs in it suggests as hl mentioned that there must be some short in the connections that I have missed so as you have suggested next week I will go back through systematically and diagnose it I have the wiring diagrams but in this case they are not much help.

[Barry B./ Ma.]

Maybe both filaments are going on in one of those bulbs because the pigtails are touching, disconnect one bulb and see what the ampmeter reads.

[Tom Wesenberg]

I think Barry may have hit it. Look at the filaments through a welding helmet and see if both are lit. Only one filament should be lit at any time, no matter where the switch is positioned.

[todd3131]

The only problem with the theory is I have both high and low beam

[BILL WILLIAMSON]

Along with this discussion, keep these 3 facts in mind:
1 EXCESSIVE DRAW = A component that draws, (uses) more amps than it should.
2 SHORT=A negative wire or source that touches, (grounds out) to any metal, (frame, body, or any power train metal, etc) which is positive, resulting in blown fuses, smoking wires, HOT connections, etc.
3 The Ammeter merely registers what is going into or out of the battery.

Many times electrical problems are incorrectly labeled as "SHORTS" A true SHORT on an UN-FUSED system can destroy wiring & even cause FIRES!! Bill W.

[Tom Wesenberg]

Any idea what bulbs are in the headlamps? Stock type, or halogen, and what number?

[H. L. Chauvin]

Hi Todd,

Not sure if you completely understand what Barry is kindly suggesting & what Tom is kindly agreeing to in your situation. Many past repro headlight sockets in the past were realy bad news.

This may help only "if", (& saying again, only "if"), you do not see what Barry is getting at:

1. Please refer to relpy #3 above.

2. Then look at your light switch position for item 2a. Bright headlights + taillights; & item 2b. Dim headlights + tail lights.

3. Now if you turn your switch on the steering wheel to obtain headlights lights like that of "either" item 2a. or item 2b., and the individual separate wires in the headlights are incorrectly touching one another in the headlight socket(s), you may be incorrectly providing volts to both the Bright Headlight filament "&" the Dim Headlight filament within the headlight bulb at the same time; hence you are turning both Brights & Dims "ON" at the same time.

4. Furthermore, this incorrect touching of wires could occur in the Driver's side headlight, or the Passenger's side headlight, or in both of your headlights.

5. Each headlight bulb has a bright filament & a dim filament where each should light up separately; however if wires are touching in one or both of the headlight sockets, "both" filaments will light up, draw "more" volts, & cause you ammeter to naturally register a drop in amps.

6. As you already proposed, your performing suggestions in reply #3's item 4. & 5. above will give a clue if a problem occurs with one or both headlights or what ever the switch controls in the On/Off position.

7. Bill W's reply #14 is correct in that we often incorrectly refer to "Excessive Draw" as a "Short". His dog Buster T agrees with Bill W. because he would have corrected Bill by now.

Have sincere confidence you can find it & resolve it. Many are anxious to later hear what you find.

[Patrick L.]

What they are trying to say is that at times the connectors touch each other when they shouldn't causing both high and low filaments to light at the same time. Like has been mentioned, unplug/disconnect each light one at a time and see which [or both] lights are giving the trouble. The headlight connectors/connections can be troublesome, as mentioned. Also we only made mention of the high charging rate, because, 15 amps is too high.

[todd3131]

When I get home next week the only reproduction part is the harness everything else is now including the insulators in the headlight sockets. I set the amps to 15 because I was on a trip that involved a lot of night driving I will set it back once I locate this demon

[todd3131]

That is what happens when I type on my phone. The parts are nos spell check got to love it
Todd

[todd3131]

one question I have is what should the amp draw be for the stock headlight bulbs typically?