I have an 82 D150. Its not a diesel, but I thought charging systems might be the same.

I have replace alternator, regulator, and ceramic resistor 3 times. Its over charging. 16 at an idle, and 19 a 2000 rpm.

As it turns out (after talking to a mechanic) on these dang Dodges, if you replace a regulator you also have to replace he resistor. Both are externally mounted.

I did that. I also found a couple wires that had been seriously heated and melted the insulation. I cut and replace them.

Now? After about 8 hours not driving, my battery is drained and it wont start. I have trouble getting a good connection on the battery post's with cables. I have to put the negative onto the engine block to get a good connection to jump off of.

I put an ohm meter on it and tested the system. I am getting a reading (with key off) from + battery post to engine, frame, and firewall of 13. Same as between the two battery post's.

I pulled the fuses one at a time, with no change on reading except one of the extra blocks in the fuse box. It went from a 13 to a 7 when I pulled the stereo memory lead from it.

Is this a ground problem and maybe a short problem? Other than replace the harness (its too dang cold out now to do it) or trace out each section to see if I have a shorted wire, the only thing else I know to do is put a battery disconnect switch in.

The alternator is still over charging, but it isnt blowing regulators everyday!

Thanks.

 

Run a ground wire from the regulator to the engine.

 

Voltage is not your main concern. Its the amount of Amps it is drawing.

 

"I have trouble getting a good connection on the battery post's with cables. I have to put the negative onto the engine block to get a good connection to jump off of."

This should be your first clue. Check/replace your battery ground cable, and your engine to ground. If the alternater can't "see" the battery it will put out full charge voltage.

One thing at a time and you will track it down. Good luck.