TheSamba.com :: View topic - Generator to Externally Regulated Alternator 1972

Tue Apr 24, 2012 8:15 pm

I know, I know. You're thinking why do this. Everybody does a internally regulated alternator conversion. It's been posted here a zillion times and is easy as heck.
One problem though. I had a '72 SB in need of an engine and I had an engine from a wrecked '73 sitting right there with an AC/ Delco alternator. Wasn't going to spend money on a rebuilt alternator and parts, tear the thing apart, blah, blah, blah.
I downloaded the wiring diagrams from both '72 and '73 from this site for comparison. What a great resource! Looked easy enough I thought. Until I realized I didn't have enough wires coming back to the alternator. I contemplated pulling the harness from the '73 and swapping it into the earlier car. Easier said than done. Between the foam and the hold down tabs it didn't look good. Plus the '73 was 100 miles away at my other place.
My solution was rather simple and didn't cost hardly anything. I had a piece of heavy stiff wire like you'd use for a clothesline only heavier. I removed the trim panel from the rear driver's side and fished that wire through the foam to the engine compartment. It wasn't easy. That foam is seriously tough! I was careful to stay away from the stock wiring and poked around toward the outboard side until I felt it go through. Then I bent a hook in the end at the engine compartment and used electrical tape to secure a piece of wire to the hooked wire long enough to reach from the alt. to underneath the seat on the driver's side back seat. Pulled it back through and ran it through the grommet where the other wires went.
Back at the alternator I used those right angle female push-on connectors in place of the multi plug at the brush holder connections. The large red wire with the white stripe had a ring connector on it already. It connects to B+ on the alternator. The small black wire could also be hooked up here. It goes to the test plug on the firewall. I just clipped the connector off and let it alone. The green wire goes to terminal DF, the brown wire goes to D- and the new red wire that I fished through went to D+
Inside the car I cut off the ring connectors on the 3 small wires. I replaced those with push on female spade connectors on brown, green and the new red wire. On the blue wire to the idiot light I just cut off the connector. The three large gauge red with white striped wires got joined with a stereo cable type connector and covered liberally with electrical tape. The blue wire I piggybacked onto the new red wire with a scotch lock.
I had taken the alternator number and matched a voltage regulator to it. That was a $50 bill. I had let a friend have the one out of the wrecked car years ago so I was screwed. Finally I plugged the spade connectors into the matching color wires in the reg. multi plug. There were 4 wires but the blue lead from the reg doesn't go anywhere in this setup.
Anyway, that's my story. For $50 I was able to use what I had and so far it's working great. Poor people have poor ways, as my grandma used to say.

Tue Apr 24, 2012 8:53 pm

Thats why ya got a handle like Picketwire huh..cause ya done fixed the bug for gramma with picketwire onna count she was poor,and now she's a pimprollin in a fine ass bug fixed with clothesline.

Tue Apr 24, 2012 9:16 pm

You probably don't want to hear this right about now but there is actually several unused wires already running from the engine bay through the main loom to under the back seat.
They are part of the diagnosis system.

That's how I've converted a couple of 71-73 cars to externally regulated alternators.

The black wire from the alt up to the diagnosis plug gets joined to one of the unused wires and the other end of them comes out next to the regulator.

Saves having to run an extra wire.
Not much use to you now I know but incase anyone is in the same situation its an easy option.

They are also handy for running sender wires for extra gauges.

Wed Apr 25, 2012 5:27 am

I couldn't find that other end of the black wire coming into the car. It terminates at the test plug I think. That's why I ran the other wire.
I'd be interested to hear where the extra wires are that you used to wire accessories.
Seems like I always do things the hard way!