72 C-10 Charging issue

[heighway77]

The truck has a new alternator, battery, and voltage regulator and still will not charge the battery. The Battery is securely grounded to the engine block. Could there be a bad ground somewhere else that is causing this? If so would anyone have a link to the wiring schematic for a 72 C-10 with a 307? I did notice there is a ground that is connected from the frame to the body that is broken...could that be it?

Thanks ahead of time...I think the guys at the parts store are tired of charging my battery every 3 days :-).

[KB71C10BBSUPER]

Is your voltage reg. a new transitor type or the old mechanical one. It is possible you need to adjust the voltage reg. If you change over to the newer delkatron style (73 to 80internally reg. style) you will find that it charges better with less pulsation when the lights are on. It is faily easy to change over. Or you can buy a One wire that will just bolt on. Hook it to the Postive and your done. I have found those take a bit of RPM to start charging though.
Hope this Helps
K.B.

[heighway77]

I am not sure if it is the same as the old voltage regulator...they look the same and have the same number of pins. I got it from Advance Auto.

http://shop.advanceautoparts.com/web..._R|GRP60003___

[KB71C10BBSUPER]

Does it have 2 screws that hold the cap on. or fixed rivits. The ones that have the screws are generally the mech. type the rivit type are transistor type.
If it has screws then it is adjustable. Before you go there check your white and blue wires from the alt to the reg and see if there is continuity and also the Red power wire. I have seen them break between at times.

[VetteVet]

This may not solve the problem but it is the diagram you asked for. You should not have to adjust the voltage regulator to get it to charge.

[68gmsee]

Originally Posted by heighway77

The truck has a new alternator, battery, and voltage regulator and still will not charge the battery. The Battery is securely grounded to the engine block...............
Thanks ahead of time...I think the guys at the parts store are tired of charging my battery every 3 days :-).

First thing I would do is to verify that the alternator is in fact working properly. I'd take it to a shop that specializes on that. Just because all the stuff is new is not guarantee that it's working properly.

If the alternator is working then I'd put a meter across the battery terminals and see what kind of voltage I'm getting. Between 13-15 should be okay. If it's not, then you may have a defective voltage regulator. I went through a couple of new ones a few years back.

If all of the above is okay. Then it's possible the cables to the battery are defective. They corrode internally where they meet with the end that clamps to the battery. Also happened to me.

[71swb4x4]

New parts aren't always "working" parts. Have them checked out. Don't randomly replace parts without having the old parts checked first.

[Repothis]

This happened to someone a while back and they brought their truck into me to check it out. The alternator that was on the truck was internally regulated and only had one wire ran to it. The bearing started making noise so they got another one. What happened was they hooked it up the same way but the new alternator was externally regulated.

Basically check all your wiring and make sure the small din plug is plugged in and plugged in ALL the way, his clip was a little worn out and had worked itself back out of the alternator just enough to not have a good connection. Doesn't sound like this is your problem but thought I would toss it out there since this did happen to someone else. Seems simple but solved the problem.

[heighway77]

I took the alternator in and it checked out ok. That is how I found out the "F" Blue and "R or 2" Black wires were not wired to the voltage regulator (initially there was only the red power wire connected). When hooked up to the machine that tested the alternator if the 2 wire plug was not connected it was not charging.

One thing I noticed looking at the wiring diagram - there are 4 wires connected - there are only 2 wires going to the plastic connector that plugs into the voltage regulator F and 2 Blue and White respectively. Are all 4 wires necessary?

The negative battery cable appears to be good on the outside...is there a way to determine if the wire is corroded without splitting open the wire?

Thanks for all the responses so far...I feel like I am finally getting somewhere with this and having some fun doing it.

[DANTIP]

One quick troubleshooting method is to test the voltage at the battery when the engine is running. Should be around 14. If you get around 12 you can conclude that you have a problem with the charging circuit. Otherwise the system may be charging but your battery may not be able to hold the charge.

Good Luck!

[Repothis]

I don't know a ton about voltage regulators but took a peek at mine for reference I have a 70 c-20 but all four wires to the voltage regulator are hooked up and two went straight to the alternator to the little gray plug. I didn't have time to really chase the other two wires off the regulator back to where they are running but they are hooked up.

[VetteVet]

Here is a conversion from the FAQS that will answer your questions and tell you how to wire in an internally regulated alternator if you decide to go that route. If you have an idiot light dash it will be a direct swap, however if you have the ammeter dash you will need to wire a resistor in the brown wire as the internal regulator needs to see some resistance to tell the alternator to charge.
http://67-72chevytrucks.com/vboard/s...d.php?t=119379