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Lights

840 Views 12 Replies 5 Participants Last post by  docvette
In my 1970 nova i just replaced the head lights and they burn real dim, my brother in law who works at advanced auto parts told me that it was bad voltage. Im not sure if it would be the alternator or the wire's any help would be great.
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first thing you gotta do , is what the voltage is at your lights, should be 12 to 14 volts. Or use your test light and compare the brightness at the lights and at the battery. If the voltage is up, then it's either a poor ground or the lights aren't connected to the terminals. Asumming you got the three hole ( prong ) connectors yet it should be correct if it was correct before. How were the old ones?
If you have correct voltage coming to them, I would also chase a bad ground. Check the ground for both sides, as one may cause them both to go dim.
When i put the test light on the battery it is real bright, and when i stick it in the plug in it is not as bright but not dim either. And the other lights were blowed.
2
Doc here, :pimp:

Do you have a DVOM..or can you borrow one?

If so, start and warm your car..let it run at least 5 minutes, to replenish the load from the "cold start" your starter took out of the battery..

With the engine running and no load on the system..everything off, set your DVOM for DCV, Scale for VX50 , and measure the battery voltage, it should read between 13.95 and 14.4 Volts. If not, and the running check is 12 volts or below, your alternator is headed south..rebuild or replace..

If it IS between 13.96 and 14.4, then load the system with the headlamps..let it run a few seconds and measure again, if the voltage is below 13,95 the diode regulator is going south..rebuild or replace..

You can either buy a new one , ($39.00 to $250) or get a kit, ($20) and rebuild it yourself...I advocate the rebuild..you already know it's right for the car, and Fits..and you'll end up with a much better unit then over the counter parts today..(Poor QC on new Electrical Parts now a days. many out of the box failures) If you decide to do that, I can give you step by step directions , and there is an article on the WIKI, I wrote, you can read. It's easy to do , only takes a few hours of your time...





If you find the Alternator to be good, and the grounds are good, you could have an issue with the switch gear going out..

The Headlamp switch as well as the High Low beam switch may have burned contacts as well as loose terminals..


If that is the case, you should consider running headlamp realys..This takes the load OFF the switch gear and AT LEAST doubles the headlamp brightness..A Good Saturday project!

Doc :pimp:

BTW:Good Post! :thumbup:
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that's kinda what I was trying to say, and take a good look at the dimmer switch connections.
docvette said:
Doc here, :pimp:

Do you have a DVOM..or can you borrow one?

If so, start and warm your car..let it run at least 5 minutes, to replenish the load from the "cold start" your starter took out of the battery..

With the engine running and no load on the system..everything off, set your DVOM for DCV, Scale for VX50 , and measure the battery voltage, it should read between 13.95 and 14.4 Volts. If not, and the running check is 12 volts or below, your alternator is headed south..rebuild or replace..

If it IS between 13.96 and 14.4, then load the system with the headlamps..let it run a few seconds and measure again, if the voltage is below 13,95 the diode regulator is going south..rebuild or replace..

You can either buy a new one , ($39.00 to $250) or get a kit, ($20) and rebuild it yourself...I advocate the rebuild..you already know it's right for the car, and Fits..and you'll end up with a much better unit then over the counter parts today..(Poor QC on new Electrical Parts now a days. many out of the box failures) If you decide to do that, I can give you step by step directions , and there is an article on the WIKI, I wrote, you can read. It's easy to do , only takes a few hours of your time...





If you find the Alternator to be good, and the grounds are good, you could have an issue with the switch gear going out..

The Headlamp switch as well as the High Low beam switch may have burned contacts as well as loose terminals..


If that is the case, you should consider running headlamp realys..This takes the load OFF the switch gear and AT LEAST doubles the headlamp brightness..A Good Saturday project!

Doc :pimp:

BTW:Good Post! :thumbup:

Excellant info Doc! I might just rebuild my altenator for kicks
If I had the car here in front of me , I could fix it, but as you can tell, I gotta had time tellin sombody else how. Anyway question for Docvet: do they still make a conversion kit to change the alternator to a one wire setup, any experiance with this ?
Doc Here, :pimp:

CAMEROFIEND,

Thanks!..Actually it's not a bad idea to do every 5 or so years, If your so inclined..or at least replace the brushes an inspect the alternator, (but the kit IS better, If your going to open the cases anyway..)

KNIGHTHAWK,

On a GM Internally Regulator, type alternator, It's simple..just remove and abandon the charge light wire, Brown or #2 wire, and remove and abandon the small red wire,#1, then make a small jumper from the Big red wire #1(alternator output) to the small red #2 terminal..you have a one wire.



Doc :pimp:
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Thanks everyone I will do this and see what happens.
Doc here, :pimp:

Keep us updated! :thumbup:

Doc :pimp:
Hey Doc,
Is this kit readily available at my local Autozombie or do I have to go to NAPA for it??
Thanks
Doc here, :pimp:

The Kit shown, Is one from Kragen, (which is also Checker and auto zombie) , NAPA has them too but will charge you $10 bucks more for the same kit :mad: :mad:

Doc :pimp:
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