I just pulled the ac box, condenser, etc, the whole shebang from a donor truck at a u-pull-it yard... got everything out intact including templates of the firewall and core support with the holes I need to make.... Putting the stuff together will not be my problem...

I really know about nothing when it comes to ac systems and how to make sure the pieces I got are good. Does anybody know how to test the condenser and such before I put everything in and fill the system with refrigerant, or do I put everything together and cross my fingers?

Also I have a 90 5.0 motor with the serp setup and 5.0 compressor. I know I will need custom hoses to connect the components up. What about refrigerant... do I need to convert from 5.0 stuff to a more modern refrigerant? do I need to make changes elsewhere as well?

As for wiring... already have a painless harness in the thing, so I am not too worried about that aspect....

 

I am a licensed ac tech, and I will say take these steps: for the condenseer, make sure it is leak free, pressure it up and leak test it in a water tank or something similar, same for the lines and evaporator, the dryer and expansion valve NEED to be replaced with new ones, the compressor should have 2 valves on it to isolate it. Make sure that these turn freely and try to leak test the compressor as well, be sure the front seal is good, it isn't froze up, and those valves open and close. The lines could be leak tested as well.

If everything tets fine for leaks, then make sure you don't have a bunch of gunk built up in the system, like stop leak and other additives that do nothing but plug systems up. If you are clean put it together... If not clean all the cr@p out of the system with solvent.

Replace the o rings and the check the De ice switch, It was spec'd from ford to open at 20* and close at 40*. Make sure to put the correct oil in the system (mineral oil) and the right amount, this is determined by a dipstick that you dip into a plug in the compressor housing. You have your work cut out for you.

Try for all you can to charge it with R12. R134 will blow plenty cold, but heres what happens. R134 is a smaller molecule, and therefore it carries heat less effectively as the r12. R134 will carry plenty of heat (or energy) to make a cool cab, but you need to remember that the r134 systems have minimal rubber lines. Our old fords have all rubber lines, this causes a bunch of leaks so small you won't ever find them but they leak your freon our annually.

 

Warhorse thanks for all the info. I did not expect this to be easy.... how much pressure should I use to test the components in psi? Where are the dryer and expansion valves located? Are the part of the compressor? Sorry, but I really am a newbie on this stuff.... Since I am using an 90 mustang compressor, but the rest of the components are 78 Ford, I will need custom hoses... Since I already have to go that route, what type of hoses should I get that are R-134 compliant? Is the 90 mustang r-12 as well? Will I need a conversion kit?

I guess I will start with putting pressure to one line for the condenser and evaporator and see if gunk spurts out.... I am guessing I do the same thing for the compressor too.... Then what is the best solvent to wash with?