Squareback alt with one normal and one large spade connector

[DenisMcG]

I am bringing a neglected 68 Formula S 383 back to life and have run into a few electrical problems. When I got the car, it had an upgraded electronic ignition and an electronic voltage regulator but an older style roundback single field alternator. I know that this will not work so I bought a new squareback dual field alternator. The alt has two different spade connectors, one large and one small. I found out that the large connector is grounded after I melted a jumper wire when I tested it in the car. I assume that this squareback has actually been rebuilt to work with a single field system. I will return it tomorrow, but what year of car should I get the alternator from?

Thanks for any help,

 

[67Dart273]

I'd ask for about a 72, and take your multimeter and check it on the spot. Even if it looks OK, "rebuilts" have a reputation.

 

[skykeith]

Just get one for a 1973,74,75 model car and check to make sure neither terminal is grounded to the case. Rebuilders seem to be converting more of these higher output squareback alternators to work with the early style regulator. All they do to convert it is leave the insulating washer out of one terminal.

 

[BillGrissom]

You can get an electronic Vreg for both types of alternator. If yours has a triangle connector w/ 2 pins, it is for the later "isolated field" alternator w/ 2 field terminals. It sounds like you do have 2 field connectors in your wiring harness, so probably is.

 

[DenisMcG]

I decided to isolate the grounded terminal and everything is now working. I am getting 13.5 to 14.5 volts depending on rpm. So that part is done. Now it is onto the instruments and steering wheel.

Thanks for the tips.