I can't get the charging system on my d600 truck to work. I have replaced the alternator and the voltage regulator. The alternator will put out charging voltage if 12 volts is jumpered directly to the field winding but nothing when hooked to the regulator. The regulator has battery voltage at the I term and puts out .1 volt to the field winding of the alternator. Have replace the regulator three times to no avail.

Any ideas????

 

Does the alternator have an internal regulator that you are using? On my 74 J10 I wired the Alternator right back tot eh battery and never had any issues.