lights flickering

I have a '74 Super, and I am having problems with the headlights, and dash lights, flickering, occasionally. It does not happen all the time, but when the lights flicker, the generator light comes on, and the headlights and the generator lights are very bright, and the flickering is at a constant rate. There does not seem to be any particular event that occurs to start, or stop, the flickering. Once the flickering starts, it may stop in a couple seconds, or last until the car is turned off.

I am looking for suggestions on what I should look for.

Reply to
Nellis
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US '74 Supers had an alternator. Does your engine have the original alternator or has a generator been substituted, or even a later alternator?

First step, I would connect a multimeter across the battery posts so you can monitor the charging voltage as you drive.

Normally, it would sit rock-solid at something like 14V (range of 13.5 to 14.5V. If it goes above

14.5V when the lights brighten, the regulator is not working correctly, for whatever reason.

Try to find out just what charging system is installed.

Speedy Jim

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Reply to
Speedy Jim

Are you still running the 4 wire Motorola alternator(two connections, one has 3 wires and the B+ lead) or has it been converted to a single- wire internally regulated alternator(one wire, usually a spade connector and the B+ connection with a ring connector)?

Chris

Reply to
Hal

Check the brown negative ground wires. Maybe it has a loose or bad connection. Check where the brown wires connect in front of the gas tank. These links might help:

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Apr 2, 11:50=A0am, Nellis wrote:> I have a '74 Super, and I am having problems with the headlights, and> dash lights, flickering, occasionally. It does not happen all the time,> but when the lights flicker, the generator light comes on, and the> headlights and the generator lights are very bright, and the flickering> is at a constant rate. =A0There does not seem to be any particular event> that occurs to start, or stop, the flickering. =A0Once the flickering> starts, it may stop in a couple seconds, or last until the car is turned> off.

Reply to
Jim347a

The alternator is the two-post Bosch AL82N. Not sure how old that is. I will check the voltage across the battery tonight. The only problem that I have now is that for some reason the headlights are no longer working. It could very well be a ground wire. I will check those connections as well.

Thanks.

Reply to
Nellis

If both side headlights quit at the same time, it's more likely something common to both, such as the dimmer relay or the Ignition switch.

This page of my web site:

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for: "Headlight Dimmer Relay circuit '71 thru '79."Has a simplified diagram. Speedy Jim
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Reply to
Speedy Jim

Jim and Hal,

Thank you both very much for your comments. I wanted to let you know what I found:

  1. The problem that I was having with the headlights not working turned out to be a faulty headlight/dimmer switch. After replacing that, I was back to the original problem.

  1. Now that the problem was occurring again, I ran the voltage test across the battery. While idling, the volt meter read about 14-14.5volts. When the lights got brighter, the voltmeter read 20v. So, the problem is probably the voltage regulator. After some searching, it appears that the voltage regulator is missing - hence the problem.

I am ordering a voltage regulator now, and we should be all set. Thanks again for all your help.

- Nellis

Check the brown negative ground wires. Maybe it has a loose or bad connection. Check where the brown wires connect in front of the gas tank. These links might help:

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Apr 2, 11:50 am, Nellis wrote:> I have a '74 Super, and I am having problems with the headlights, and> dash lights, flickering, occasionally. It does not happen all the time,> but when the lights flicker, the generator light comes on, and the> headlights and the generator lights are very bright, and the flickering> is at a constant rate. There does not seem to be any particular event> that occurs to start, or stop, the flickering. Once the flickering> starts, it may stop in a couple seconds, or last until the car is turned> off.

Reply to
Nellis

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