I have an odd problem with my 64 Polara that i have tried to troubleshoot for quite some time. Im not very good at working on the electrical system so im in need of assistance.

The problem is that the car overcharges at around 18V. When you fire it up, it charges 14 ish for about 2-3 minutes, then just accelerates up to 18V.

I have replaced the voltage regulator and that brought the charging down to 16.5-17.5V for a while, but now it seems to be around 18 again.

I have measured at the alternator and the outgoing current is the same as what im measuring at the battery.

i seem to have a 1.20V voltage drop between the positive battery terminal and Ign1 on the regulator, this is bad i guess?

Could it be the actual alternator that is bad?

 

Od -

I'm probably worse with electrical than you are, but is they any way you're over rotating the alternator, with the wrong size pulleys?
And just because you got a new voltage regulator, doesn't mean you got a good one.

Archer

 

my money is on the VR; they put out total crud these days. i'd get a few of them man, and replace as necessary. to my mind, it's the only thing it could be.

 

Clean all the grounds... Alternator / Regulator / Battery / Engine to Firewall / Chassis to Body / Also make sure all the wires are in good shape and connections are good and solid on the wire and mounting screws.. Are you sure the battery is in good shape also... Not discharging over night?
I think if all that is good, You still have a regulator issue...
Keep us posted..