I981 GMC K2500 alternator

[Jahwarrior007]

Good Sunday to all,

Just replaced my busted clutch on my '81 4 wheel drive. Anyway, before I took out the motor and before I changed the clutch, I'd bought a new alternator and it was ok. Now the needle moves from 12-13 back and forth to 18 volts. I did try and check the wires, all looks ok it seems. Plus my temp gauge isn't working when before it did. Anyway, I've got other wires that need to be put back in place. Tried to use schematics, but they only give me headaches. I've taken out the A/C since it is my "work" truck. Thanks for the help.