Alternator and voltage regulator

Senator Leahy

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Stupid question

If the alternator (brand new) has an internal volt reg is it possible to bypass the volt reg on the firewall? I don't have an elec ign...yet. So far something has burnt up my volt reg on the firewall and the ballast resistor. I'm getting 12.4 volts charging which doesn't seem like much without the volt reg on the firewall.

Another thing
When I first started the car it peaked at 18v without the volt reg on firewall now it's back down to 12.4. What could have caused it to spike momentarily then go back down?
 
Ditto on the lower taxes and second amendment rights.

You have a wiring short somewhere... Throwing a new alternator with a built in regulator isn't going to help matters (I'm assuming you want to put in a 1 wire POS GM alternator) and if anything it will make things more complicated.

As I said in the other thread, disconnect the Painless fuse block first and get your starter and alternator circuits right first.
 
The new alternator had the internal volt reg, I didn't buy it to bypass the external one. I was just wondering if bypassing the external volt reg could be done. So far everything seems to be working fine without it but the charge is at 12.4 at the battery.
 
The new alternator had the internal volt reg, I didn't buy it to bypass the external one. I was just wondering if bypassing the external volt reg could be done. So far everything seems to be working fine without it but the charge is at 12.4 at the battery.

Make sure that the case of the alt. has a ground on it. If the alt isn't grounded it can cause trouble with charging.
 
The new alternator had the internal volt reg, I didn't buy it to bypass the external one. I was just wondering if bypassing the external volt reg could be done. So far everything seems to be working fine without it but the charge is at 12.4 at the battery.

You can't run both... If you have a new alternator with the internal voltage regulator, you have to wire the charging system correctly for that alternator. Basically.. toss the original voltage regulator and charging system wiring and start from scratch.
 
I had the same issue (without the internal voltage regulator in the Alt though) and it turned out to be a couple melted wires in the power block on the firewall. I pulled it out, removed and replaced the block and cleaned all the connections and voila. Of course now I am charging too high at 15.15 at the battery so I probably need to adjust the voltage regulator down a bit.

This link shows why the two wires burned up and how to fix it in a more permanent fashion.

http://www.allpar.com/history/mopar/electrical.html

Good luck!
 
I had the same issue (without the internal voltage regulator in the Alt though) and it turned out to be a couple melted wires in the power block on the firewall. I pulled it out, removed and replaced the block and cleaned all the connections and voila. Of course now I am charging too high at 15.15 at the battery so I probably need to adjust the voltage regulator down a bit.

This link shows why the two wires burned up and how to fix it in a more permanent fashion.


http://www.allpar.com/history/mopar/electrical.html

Good luck!
do you have pics of the upgrade and what you did. the link kinda makes sense i just want to be sure i do it rightby see what someone did.
 
do you have pics of the upgrade and what you did. the link kinda makes sense i just want to be sure i do it rightby see what someone did.

I have yet to do the upgrade with the new wiring (But I will be doing it), for now I simply removed the power block on the firewall under the master cylinder and found those two wires were burned up. I happened to have an extra power block from my parts car so I swapped the two, one wire at a time. And replaced the two connectors for those burned wires.

I will be taking her out tonight or tomorrow and will snap pics of what I did. I was able to see those wires were melted/burned without removing anything though, just by looking you will probably be able to tell if this is an issue for you.

To clarify, when I say power block on the firewall I mean this:
http://www.allpar.com/images/mopar-photos/electrickery/1.gif

The two arrows in that pic point to the wires that have this problem.
 
Also, I was able to see 14.4 volts at the fusible link that comes out of the power block, but only 12.5 at the battery. This helped lead me to the burned wires. Again, will try to snap some pics tonight or tomorrow for you.
 
I took some pics and can't upload them from the iPhone for some reason so I will have to do it tomorrow. Stay tuned.
 
Hopefully I can walk you through the three pictures here and maybe they will help you get to your charging issue.

In this first picture you can see the power block on the firewall. I have circled the fusible link. When I disconnected this link with the car running, I was able to get 14+ volts on the alternator side and only 12.5 on the battery side. This told me the charge was making it this far and something between here and the battery was shorted/corroded/burnt/etc. When I traced it to the power block I noticed the first melted connection.
Power Block on Firewall.jpg

This is the old power block removed showing the burnt connections for the "P" and "J" connections. This was easily noticeable when removing the middle harness from the power block.
Old Power Block showing trouble spots.jpg

Here is a shot of the back of the power block once removed from the firewall. Not sure how helpful this is but you can see how nicely labeled the power block is! You can also vaguely see the burnt/deformed connectors just not as well as you can from the front.
Rear of old power block where P and J burnt up.jpg

Power Block on Firewall.jpg


Old Power Block showing trouble spots.jpg


Rear of old power block where P and J burnt up.jpg
 
Oh, the hardest part for me was figuring out the connectors. I think they are "Packard 56" connectors. For the male side you need to use a pair of needle nose pliers to squeeze the male blade together so you can pull it out of the harness.

For the female side you need a small screwdriver to bend the metal tab up slightly and the connection will also slide out.
 
Thanks for the pics. The setup in the bulkhead is a little different on my 65 New Yorker but I should be able to use your pics as a reference to what's going on with mine.
 
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