Charging System Help - 1949 Series 62

[Joe Jensen]

I am trying to diagnose a problem in my charging system.  I have read the shop manual and a supplement manual from Delco-Remy regarding the voltage regulator.  Looks like I could use a variable resister to test the charging system.  Not sure what to use.  Does anyone have a suggestion?  I found the following online:
https://www.parts-express.com/elenco-resistor-substitution-box-kit--320-076?gclid=Cj0KCQjwufn8BRCwARIsAKzP697tSV-kMd1RNUdpHkNXn-HqMAN30P1Oni6g170IEmLrcj-C31kmVxwaArWDEALw_wcB

As far as the problem:  I had the car die on me the other day driving myself and family home from dinner.  It was dark so head lights were on and the car died when the battery drained.

I charged the battery, cleaned the contacts on the voltage regulator and checked the air-gaps.  Re-installed and was checking voltage and adjusting while running head lights and while not running head lights.  Everything seemed ok.  Upon another restart with head lights on found that the system was not charging (no voltage on Gen terminal and no AMP draw on Wire coming from A on generator).  Battery drained down to near 5 volts with no change.  Restarted again and it all was working making over 6 volts.

Thank you for any help.

Sincerely,
Joe Jensen
‘49 Series 62, Club Coupe

[Jay Friedman]

A simple first test.  Ground the field terminal on the generator.  Using a jumper wire with alligator clips at both ends, the way I do it is to connect the field terminal to the nearby unpainted steel fuel line between the fuel pump and carb.  Then rev the engine a bit.  If the ammeter now shows a charge, the problem is in the regulator or the wiring.  If there is no charge the problem is in the generator. 

[bcroe]

In my generator days, the most common failure by far was worn out
brushes.  Not hard to change.  Bruce Roe

[Joe Jensen]

I have grounded the field wiring and the generator output jumps to about 30 amps.

Thanks,
Joe Jensen