I found a A/C system out of a 4runner for sale for $125 for everything. Only problem is I dont personally know the person selling it. I want to be sure I am buying working parts, Is there a way to tell if the parts dont work, or if everything needed is there to swap it into my 93 single cab? Also, I plan on taking it to a mechanic to do the work, how hard is this installation to preform for a ase cert. mechanic?

 

No one has any advice or suggestions?

 

wont know if the compressor works till u put it in and fill it up... best to buy new ones cuz 4 out of 5 dont work

 

The compressor is the big issue, if it turns freely, no roughness, oil clean, you can feel suction and pressure while turning it, possibly it'll be alright, if not its still easily repaced with a new or rebuilt unit.
As for the rest of the stuff, the condensor in front of the radiator, is just a radiator for the AC, is it visually OK?, you could pressure test it to see if it leaks, all the lines, hoses, belt, pulleys, brackets, wiring harness, relays, switches, duct work, evaporator unit under the dash will be needed, reciver dryer is a throw away and needs replaced anytime the system has been opened and exposed to air for any length of time.
Install is a job, but could be done by someone with experience as dealers added them all the time, then the system will need filled, 94 was the change over year from R12 to 134A so don't know which you will have from the donor rig, but that can be spendy for R12, then the system will need evacuated and charged once completed with the install.Be prepared to spend a few bucks to get it done. Good luck.