Voltage Regulator Question

[Gianyveedub]

Hey all, I am having some difficulty figuring out a problem with my trucks electrical. I have put a new regulator, alternator(tested) and battery. The truck was reading below 12v and would drop the longer it kept running, even if I revved her or drove on the freeway. I tested all the wire according to the 1963 Chevy Shop Manual and got no where. I was reading online and someone said to add an extra ground from the alternator to the body. See as how mine was wired like that already I tried it and now she charges to about 15v when revving around 2500....however, if I take the negative cable off while idling, she dies. If I rev her to about 1200 to 1500 and then have someone pull the negative cable off she will still run until I take my foot off the gas. Can anyone tell me what is wrong of if it is now fixed and I should just be happy, Thanks

[Gianyveedub]

I started it just now to see if it would, it does, but when revving and letting it idle, you can hear a steady electrical whine that stops after a while but will start when you rev it. Hope this info helps.

['63GENIII]

I'd say alternator. I can't tell you how many times that I've taken an alternator in to Kragen, O'reillys or Pep boys only to have them say it's ok and it's really not. I ended up going with a late model alternator with internal regulator and never looked back. Not exactly for the purist but much more simple than stock and puts out a reliable 80+ amps I believe. Where did you get the alternator anyways?

['63GENIII]

Oops, sorry. Didn't see you got her running. The whine... I'm guessing wasn't there before? Is it a reman unit?

[HEI451]

Was it a rebuilt alternator? If so, what supplier? Some rebuilt's are no better than the old, broken part they were when they were replaced before the "rebuild". There are part stores that can load test the alternator off the vehicle,. and that should be done, but, not just a quick 20 seconds and say its OK, let the alternator run until it gets to operating temp, then, load test it.

As far as a regulator, it appears you have a remote regulator, or you wouldn't have mentioned it separately. There are two different kinds. One is a manualk type, uses points and electro-magnets to operate, and was on the truck when it was built decades ago. They work, but, not as good as type 2. Type 2 is a fully electronic regulator, no points, and works leaps and bounds better than the type 1's do.

You should always try to use the type 2 electronic ones. If you have ever seen the headlights oscillate from dim to bright to dim to bright, this is the type 1 regulator turning the alternator on and off, on and off to charge. Type 2 engages the alternator for charge, holds it that way, and drops excessive voltage to chassis ground, no oscillation, more consistent charging. Alternator electric "wear" is mostly eliminated with the electronic regulators.

The alternator itself can have a weak winding in one of the three, two bad ones, diodes out, many different things. It is interesting that you actually got 15 volts out of the system, something was working correctly on the charging when it did that, but, doesn't sound like it stayed that way.

I would have to suggest getting the alternator tested, again if it was before, even though it is a "new to the vehicle" part. I would also think that IF the regulator was the old points type, it is defective, and that do3es happen in new ones of the type 1, and/or not adjusted correctly. Old types can be adjusted, but it isn't worth the low price of the type 2, and the hassle of adjustment.

As far as grounds, yes, regulator tho chassis, and, make sure the chassis to engine grounds are in place, clean and tight. Basically, both the alternator, and regulator want to be grounded straight back to the battery. This is done by the alternator being mounted to the engine, and the regulator to the chassis, chassis to the engine, then engine to the negative battery cable.

BTW, disconnecting the battery while the engine is running, is just not advised, especially if there is an electronic ignition in the vehicle.

[Gianyveedub]

Thank you for all the replies. I should go into more detail about what I have and where I bought it. The truck has an HEI distributor ( I know someone mentioned electronic Ignition) and the alternator was bought at Winchester Auto (I had taken it back and got a new one free of charge and took the "new" one to AutoZone where they said it passed). The battery and regulator (type 1) were bought at Napa. I am just at a loss for words why it would not charge at all until that second ground was added to the alternator. when she is at idle when testing the battery and the alternator, both read 12.0v. I am lost on this issue, HELP...

[Gianyveedub]

Problem solved. For those who do or will have this issue, the solution was simple. I worked more on making sure the ground contacts were good and then I went to the auto parts store and bought the "type 2" voltage regulator that HEI451 recommended and she charges at idle and driving. Thanks for the help all and especially HEI451.