The headlights and taillights Pulse with the idle of the engine?

Hi,

It sounds like it could be related to the voltage regulator. Do me a favor. Here is a link that explains how to test an alternator. All you need is a voltmeter.

The primary purpose of this test is to determine if the alternator is producing a charge. So, with the engine running, you should see approximately 14v at the battery. Turn the lights on and then watch to see if the voltage pulses with the headlamps on. If it does, then suspect the regulator is failing.

https://www.2carpros.com/articles/how-to-check-a-car-alternator

Let me know what you find.

Take care,

joe

Hi,

Wow, that is producing a lot of power. Actually, I'm not comfortable with how much. If it is over 15v loaded, I suspect the voltage regulator is failing.

Please understand, this is only a theory, but I am basing it on what I'm seeing. I feel the voltage regulator is bad and it is overcharging. The regulator is integral to the alternator.

Here is a link that explains how, in general, to replace an alternator:

https://www.2carpros.com/articles/how-to-replace-an-alternator

Let me know your thoughts.

Take care,

Joe

Hi,

As far as the regulator is concerned, it is integral. I believe it can be replaced, but by the time you buy it and take the time, it isn't worth the effort.

Also, a new alternator shouldn't be very expensive. Check out Rockauto. Com. If you find one there, when you check out it will ask how you heard about them. Copy this number to that spot and it will get you an additional 5% off.

224117750185169165

However, I do want you to try one more thing before we replace the alternator. Make certain that the ground between the battery and the engine block is in good condition. If we have a weak ground at that point, it could cause flickering. If the ground is good, replace the alternator.

Note: We are not affiliated with Rockauto. I don't want you to think we get a kickback from them. LOL I have used them many times and have always been happy and the discount code is from online. Just trying to save you a buck.

Let me know about the ground. If you question it, run a new temporary ground between the battery negative and the engine block.

Take care and let me know how things turn out or if I can help.

Joe

Do you know which one is on the vehicle presently? There were three options. 63, 78, 94amp. What it came with I would recommend.

If you look at pic 1 below, I attached the OEM part numbers for each amperage. See if you can locate the part number so we know for sure what you have.

Also, it really makes me happy to hear someone is working on the old square-body trucks. If you look at pic 2, I restored that one in 2000. It was picked by Rockauto for a magnet. LOL

Let me know.

Joe

PS: Just to confirm. The 7.4L wasn't offered in the half-ton. I'm looking at a C20 for the info I've provided.

See pics below

Hi,

I'm glad you found it. As far as driving it, that is a tough one to answer. You don't want it to produce any more voltage. It could damage different electronics and even wiring. If it stays where it is, you should be okay. Just keep an eye on it.

Let me know if this takes care of the issue.

Take care,

joe

Hi,

Thanks for the update. I'm glad to know that took care of the issue. The voltage regulator was starting to fail in the old alternator.

Feel free to come back anytime in the future. You are always welcome here.

Take care,

Joe