This is an update to this thread...
http://www.dieselplace.com/forum/showthread.php?t=245281

I got this cheap kit off Ebay, it included the manifold, hoses and vacuum generator. The manifold and hoses were mediocre quality but the vacuum generator was a joke (Central Pneumatic brand, ie. Harbor Freight). The system had 0 pressure in it so I decided to evacuate it myself. The vac gen pulled a max of 10" hg (inches mercury). I immediately pulled off the R12 fitting and put it on my vacuum bleeder (used for bleeding brakes, etc...), that pulled 25" hg. I held it there for about an hour and got to recharging.

The kit came with no adapters and would only fit the low side (1/4"?). The high side is a little smaller and the hoses won't fit it. I have since ordered adapters for it and hope to have them soon. After struggling to find why the system wouldn't evacuate or take a charge, I found one of my hoses fittings for the shrader valve was too far recessed! I swapped hoses and it seemed to work fine.

The compressor says to use 8oz of oil and the evaporator says to use 2.5lbs of refrigerant. I had 4 oz of oil and 24oz of Freeze 12. I added one can of Freeze12 then the oil and the rest of the Freeze12. By this point it was already blowing cool and running ~20psi on the low side. Today I picked up the rest of the oil and Freeze12 I need and will add it tomorrow.... but with this hot weather, it sure is nice having AC again :)

Price:
Manifold and vacuum gen ~$80
Freeze12 and oil = ~$50 (from NAPA)
Lots of adapters ~$70
------------------------------
Total $200

I figure the local shop would have charged a little less or about the same but now I have the tools, knowledge and can do it myself.
BTW, Freeze12 is NOT flammable (says so on the can).

wow 2.5 lbs?? My truck only takes 1.6 :confused:

probably just differences in R12 vs. R134 Im assuming?

Thats good to know that it ended up working well for you...I might look into something like this because Ive had to pay to have my system evac'd and recharged twice now. (hit a deer once, broke the condensor, and second time I had to empty the system when I pulled the motor out)

I thought 2.5 seemed high but this is the first time I'm done any AC work. That is however what is said. But I read that 25psi is where you want the low side (at around 1500 RPM) so I don't think it will take that much...

25psi is just about right.....what your vent temp.?...should be about 45f to 50f...

25psi is just about right.....what your vent temp.?...should be about 45f to 50f...

I have no idea what the temp is. I'm going to guess at full blast it was around 50*F. I'll look for a thermometer to check.

BTW, Freeze12 is NOT flammable (says so on the can).

I know R134A is flammable, and FREEZE 12 is comprised of about 60% R134A by volume. The last conversion I did was for my mom's TOYOTA, and spent about $70 out of pocket for the R134A, oil, adapters, and O-ring kit. I have dual purpose manifolds with the adapters already, and my air driven vacuum pump works EXCELLENT. 25" of vacuum is NOT enough to evac the system properly, need to hold at least 28-29" for 15 minutes. Also remember to only use ESTER oil in your conversion or else your compressor will see a short life ahead.

That low side pressure is greatly effected by ambient temperature.
I bought a set of gauges from HF and had the same problem, when I opened the valve it wouldn't engage far enough to hit/open the shrader valve. Bought a replacement low side fitting from Napa and now it works great.