Posted by chriscase on Monday, September 17, 2007 at 10:32:12 :
In Reply to: Re: 1975 dodge truck posted by Gene on Sunday, September 16, 2007 at 23:29:19 :
Im serious about grounding the regulator body.
Note that the regulator has only two wires- a batt, and a 'field' that goes to the alt. Without a good ground, the regulator can't do anything with it's 12v source.
Bad grounds were a problem when that truck was 5 years old. Now the connections are another 25 years older.
Try bigger screws, with star washers on both sides of the mounting tabs- under the screw heads, and on the crew between the tab and the firewall. And/or run a wire from one screw (with star washer) directly to the alternator body. If that don't fix it, run a new wire from the field connection on the reg directly to the field of the alt.
Also, check to make sure you are getting 12v TO the reg. If not, try a jumper, batt+ to reg. Chryslers of that era had lots of trouble with wiring right at the through-the-firewall connection.