voltage regulator problems .

[oldblu65]

I'm having a problem with my '65 Chevrolet C10 / 283 engine . I have a slight discharge at idle ( approx. 600rpm's ). If you up the rpm's to about 900 rpm's , you have a slight charge showing on the ammeter . If you turn the headlights on , at idle , you get about a negative 8- 10 volts discharge showing on ammeter . With the headlights on , to get to an even ( 0 on the gauge ) situation , you have to rev engine to about 1900 rpm's . If you turn the headlights on and rev the engine , you will see some change in the headlight brightness , not a lot , but some . The truck has a new solid state regulator and the alternator has been checked at two different parts store ( three times at each place ) and it passed each test ! The battery has been checked at two parts stores and passed each time as good . I've removed two ground connections and cleaned and reinstalled them . Little improvement , if any ! I will see if I can find more grounds to clean , perhaps add a couple more in the process . The truck has new battery cables and a new starter , as well . Any and all help will be truly appreciated ! I have to admit electrical work is not my strongest point !

[madebugaboo]

A possibility is that the regulator may not be polarized enough. With the engine running, take a jumper wire and going from the battery part of the regulator to the ammeter (may spark) 2 0r 3 times quickly.
If that does not work, take the cover off the regulator and file the points connections that are in there (can use a emery board). After that take a strip of newspaper or matchbook cover and pull between the points (to remove filings). Make sure to put the cover back on before starting the engine again.
Hope one of the these suggestions work for you.

[maxwedge]

That procedure is for a car with a generator, does not apply to an alternator.

[maxwedge]

Originally Posted by oldblu65

I'm having a problem with my '65 Chevrolet C10 / 283 engine . I have a slight discharge at idle ( approx. 600rpm's ). If you up the rpm's to about 900 rpm's , you have a slight charge showing on the ammeter . If you turn the headlights on , at idle , you get about a negative 8- 10 volts discharge showing on ammeter . With the headlights on , to get to an even ( 0 on the gauge ) situation , you have to rev engine to about 1900 rpm's . If you turn the headlights on and rev the engine , you will see some change in the headlight brightness , not a lot , but some . The truck has a new solid state regulator and the alternator has been checked at two different parts store ( three times at each place ) and it passed each test ! The battery has been checked at two parts stores and passed each time as good . I've removed two ground connections and cleaned and reinstalled them . Little improvement , if any ! I will see if I can find more grounds to clean , perhaps add a couple more in the process . The truck has new battery cables and a new starter , as well . Any and all help will be truly appreciated ! I have to admit electrical work is not my strongest point !

Negative 8-10 volts on the ammeter, clear that up.

[rhandwor]

If you installed a newer chevrolet regulator with an internal regulator. The field has to be excited for the altenator to work. They use the little bolb in the dash which shows its charging for this. With an ammeter I've had to replace the ammeter in this case. They make a regulator which is self exited
with this all you need is the big wire hooked up.
A lot of external regulators have to be grounded. I've had to use a staybrite pad and buff a clean spot and reinstall. Hook up a ground wire from the body ground on the firewall to the regulator bolt. Make sure sure the ground from the engine to the fire wall is connected.
Reply what exactly type of regulator you are using and where its installed.
The previous post was good for the origonal equipment regulator.

[oldblu65]

In my original post , I said a negative 8 - 10 volts . That should have been amps . Sorry for the confusion , I guess I had a little " brain glitch " ! The vehicle has the original alternator ( non internal regulator type ) with the external regulator . The old regulator has been replaced with a solid state unit .The regulator is grounded at the radiator support . I have removed and cleaned with a file and sandpaper and reinstalled the ground . I also removed the battery and cleaned the ground wire connection point that comes off the negative post to the battery box . I have removed the negative battery cable connection at the front of the engine and cleaned it as well .

[rhandwor]

If you still have your old regulator pull the cover and look. Normally they had a small wire which burns. Put in a new wire and check you may have a bad regulator. I've got new bad regulators. Explain to parts store they may let you try another one free.
If this doesn't work ohm all the small wires from the regulator you may have a bad wire.

[Blue Bowtie]

You probably have the 37A Delco alternator. That's about the time the generator went away and alternators became standard. This should be your circuit:



If you get the cover open on your regulator, check the field relay, and that resistance wire rhandwor mentioned.

[bobss396]

I'm not familiar with thew solid state regulators, but the old original types had an adjustment inside them. But I've found it easier to chuck them when in doubt. Do you have another one to sawp out to verify if the solid state one is bad?

You may want to consider an upgrade to a 63 amp alternator in the future.

Bob

[rhandwor]

If you can't find the problem you can get any delco alternator that will fit with an internal voltage regulator. Take it to an alternator shop and they can install a regulator with a self exiter in it. Then bolt it up and hook up the main wire and it will work. They use these on some boats.