Another Charging Topic

[$500F100]

Ok. How can I tell if my alternator is working? When I bought my truck the battery was dead so I figured that I could crank it on a good battery and the just swap them out while the truck was running. Whenever I disconnect the battery the truck dies. I figured the alternator and or voltage regulator were to blame, so I replaced them with new. Same thing; I disconnect the battery and it dies. Next I go out and buy a multimeter, disconnect the harness and verify all the connections. I put it all together, and still the same thing. When the truck is off the bat voltage is about 12.2 when it is running it is about 12.4. I only need my truck to make it to the dump and back so I can unload the bed and begin restoration. Am I pulling my hair out for nothing or is something wrong here?

[rjewkes]

you might try all the under hood grounds.

[kid]

The alternator is not real bad but the truck should have stayed running if the wiring was right. The field excitation wire should have been receiving current form the alternator output wire to sustain output. Our old 65 Amp systems with external regulators put out 12.45 on average while idling.

[$500F100]

I did a full field test on the voltage regulator and I think that may be the culprit. I am going to slap the old mechanical one back on and see what happens. Thanks for all the suggestions.