Step 5: Which AC compressor to use?
A Sanden type compressor which is most likely already installed in your vehicle.
A York / Tecumseh 210 which were used in many from the 70's to mid 80's in many cars and trucks (volvos as a good source)
And the mopar RV2 which was used in many Chysler V6 and V8 cars and trucks from the 1960s to early 1980s
The sanden compressor requires the least amount of work, but does require you to remove your vehicles air conditioning. To use the sanden the AC system must be emptied of freon at a AC shop then a air line oiler is installed on the intake port and clutch wire is separated from the vehicles wiring harness. While this is the easiest route it is not the best as the sanden compressor will freeze up if not oiled correctly and does not pump as much air as a York or RV2.
The York compressor is a aluminum, twin cylinder air compressor with a oil sump which can come with V and serpentine belt clutches and comes in three models 207, 209 and 210. It can be mounted either upright or on its side depending on its location.
To identify the different models the clutch is unbolted then you look at the exposed crankshaft. A York with a shaft with a beveled edge is a 207, a shaft with a grove in it is a 209 and a shaft with a sharp edge is a 210. While any york will work the 210 model is preferable with its 10.2 cubic inch displacement. I've found the many Volvos carry the 210 model.
The RV2 is a heavy cast iron V twin compressor with oil sump and usually a dual V belt pulley. It requires more complex brackets than the York and has to be mounted upright and there is no serpentine belt clutch available. It also requires removal of a check valve from the intake. But is has a 12.5 cubic inch displacement and with its cast iron constructions I believe it can dissipate more heat and be run longer.
I am using the RV2 in this instructable as it is the first compressor I found, You can use which ever is easiest or available, because other than the mounting bracket all other instructions are the same.