From the appearance of the low-side service port adapter on the POA valve, this '68 Buick probably still has R-12, although that's a guess. I can't see the service port adapter on the high side because it isn't shown. I know you said that there are no signs of a conversion, but double check whether ...

I've been thinking about your post since you wrote it on Saturday, and I have several questions to help clear-up some things. Hello all, I need help diagnosing what I have going on with the AC system on my car. What is the model year, make, model, and engine type/size of your car, and is this a USA-...

A little bit of trivia and brief diversion, if I may: Many years ago during the 1950's, when people used alcohol (not the drinkable kind) in their cooling systems instead of ethylene glycol because the former was a cheaper alternative antifreeze, thermostats had to be changed from the then-standard ...

It's a proprietary database from which I gleaned the 8.0 fluid ounces of PAG-46 for your truck. But AllData and Mitchell's reportedly have the same information. Last time I looked, you can purchase a short-term subscription to either one for just about any vehicle. They are the same factory sources ...

The pictured vacuum pump appears to be a very high-quality piece and well worth the money. Good work on achieving a vacuum of 980mBar, or 28.9inHg. Given your location above sea level, that's just about the maximum vacuum achievable. Now that you have a high-quality vacuum pump, don't forget to clos...

Sounds good. Come on back should the owners decide that they need a working A/C system in the car. I know from experience that Missouri is humid as all get-out, so it'll probably be next summer when the heat and humidity rise to intolerable levels

Did the previous compressor fail in such a way that it sent metal and plastic debris downstream? If so, then you'll also need to replace the condenser. The specs I have for your truck call for 8.0 fluid ounces of PAG-46 with a Denso compressor. You should pour-out whatever oil comes in the new compr...

Something doesn't add up. With a low side reading of 43 PSI, it's impossible for the center-vent air temperature to be 34.1°F because the evaporator already is considerably above that temperature. I'll venture a guess that the pros on this Forum don't use an infrared "gun" to measure air t...

For a vehicle with front A/C only, a low side of 43 PSI is too high and corresponds to an evaporator temperature of nearly 50°F, which would yield a center-vent air temperature in the low 50°F to the mid 50°F range, insufficient IMHO to cool the interior on a hot day. On the other hand, a low-side r...

The self-sealing can tap that you have and/or the can itself might be defective. Try a side can tap, available from this Forum's sponsor, that actually pierces the side of the can. The self-sealing cans are beginning to develop a reputation for being trouble-prone.