I have an 86 Chevy Blazer K 5 Military. I had the (2) alternators rebuilt and installed (2) new batteires. The problem is that the alternators will not charge the battieries. When bench tested the alternators are working, but when hooked up they will not charge the battieres. Any suggestions or help on this issue. I am not sure what else to do at this point. Thank You.

 

check the wiring to the altornators, the wires should always have power going to them through the main wire that uses the bolt, check for power there

 

Also check the exciter wire (at the plug), it should have power. If that wire or connection to it is broken, your voltage regulator(s) aren't being told to activate.