When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My late '73 AC compressor is equipped with a '74 inlet/outlet block. This block has the schrader fitting located on the left side port, as viewed from the back. This port I believe is the suction line to the compressor from the VIR. The right block port goes to the front of the radiator to the condenser. The VIR has a schrader fitting on the top. Both fittings are the same thread. As I understand the AC system the high pressure side, many years ago, had a smaller schrader fitting so as not to get the high and low pressure connections mixed up.
Anyway the question at hand is how to I measure the high pressure side of the refrigerent system, or is that even necessary? I have been told to measure both the high and low pressures to ensure that the system is working properly.
Roger
True, to get a complete grasp on whats going on in the system both pressures need to be measured. But the suction(low side) is all you need to charge. Adapters can be bought to connect to the "funny" fitting.