Morning everyone, so I have a 1978 Power Wagon with a 318 LA. It's a great project except I have had this major issue. The truck when I bought it would randomly turn off when I would even attempt to drive it. Now I have another discussion on the Engine, Transmission and Exhaust thread because I am new to Mopar and I had no idea where to start. Thank fully from some suggestions from those guys and some elbow grease, I have the problem narrowed down. The truck will run 13.8 Volts when running/idle. When I start to drive it will peg my gauge to 18V and we'll thats where my gauge stops. The truck shuts off, may or may not start back up and if it does it runs like it would at 13.8.. so what am I missing? Every item that I'm aware had been replaced by me. (I.E. Voltage Regulator, Ballast Resistor, Coil, Cap and Rotor, Plugs, Wires, Battery and Alternator test good. Control Module, etc..) Soo what am I missing??? Also just want to drop a HUGE thanks to everyone in the Forum and who has responded to my discussions. Everyone has been awesome to this new member.

 

The Voltage regulator is bad...
Get another new one.... Clean the mounting area with sand paper. Use a little Dielectric grease and mount the new regulator good and solid.... Install a good ground wire to the engine and to one of the voltage regulator bolt....
Make sure you also have a good engine to body to bed to chassis ground wire's.