I need some help for a friend who has a 87 Dodge pickup with a 360 V8. He has replaced the alternator but it still only charges sporadically. Anyone have a clue or have access to alternator wiring and charging system schematics?

Thanks.

I think it has an electronic regulator on the firewall. Check that first.

A common thing to check is the mounting of the voltage regulator to the firewall. It gets its ground through the mounting points. Make sure the screws get good connections to ground on the firewall and that they get a good clean connection to the case of the regulator. If it's not grounded well, it won't work.

The other thing to check is that the blue wire going to the regulator as well as the blue wire going to the alternator both have good battery voltage when the engine is running. There are a couple of splices in the harness that could possibly be corroded and causing a problem in these two wires. Usually, if the spices have problems, there will be other electrical problems with various components under the hood as well, but not always.

-Maurice

Thank you gentlemen. My friend is watching this thread and I'll report back on what he discovers.

Check the connector on the regulator,it corrodes up, and you need to clean it and put di-electric grease in it.