alternator problems

i redid the wiring for my compressors and pressure switch this weekend. drove my truck afterwards, no problems. the next time i tried to crank it, i got nothing. i jumped it off and the battery was only putting out 12 volts, when normally the alternator kicks it up to 14 volts. so i messed around with some of the fuses under the dash and the voltage jumped up to 14 volts like it should be. still have to jump it off, runs fine, but won't crank otherwise. sometimes i hear the starter clicking when i try to crank it. anyone had this happen before, where should i start?

Double check your grounds. How old is the battery? the new compressor may be puttin too much of a load on it and it can't regenerate the power quick enough or maybe even a dead cell. OR you could have a leech on the system, check all your new wires with a test light with the ignition off and see if something is still powered.

its the same compressors and setup, i just had to rewire it. i pulled the fuses out of the lines for the compressors and pressure switch and it its still doing it. i don't know what else is pulling power from the battery. a friend of mine had a "gauge" fuse under the dash that was loose and it caused problems with the alternator similar to the ones im having. could it just be a fuse? what other wires should i check with the light if i have taken the fuse out of all the wires i have messed with?

check your lead that runs from the starter relay to the solenoid, they have a tendancy to come loose if the plastic housing is cracked or gets hot.