RV2 AC compressor Rebuild help
Correct, piston travel from TDC to BDC is 1-5/16" and the bore is 2-5/16".
It actually looks like the stroke is 1-¼". You measured 1-5/16" from the piston to the deck at BDC. At TDC you didn't provide a measurement, but it looks like the piston is about 1/16" below the deck. That would make the stroke 1-¼". If your calipers have the capability of measuring depth, could you perhaps get a measurement of the distance from the top of the piston (not the reed valve reliefs, but the machined surface) to the deck at TDC, and perhaps again at BDC? That would be more accurate than a tape measure. It would be great to have that info available somewhere on the internet :thumbsup:
Hope that helps, but since you mentioned the York compressor what are you plans?
Not OBA, if that's what you were wondering. Actually, I am using a York driven by a large DC motor for OBA (basically identical to an Oasis, but made by me), but I am not interested in the RV2 for OBA use. They're too rare and valuable for such use, IMO. In fact, I plan on using a York for the AC system on my Cummins swap, but for comparison I wanted to find out how much displacement the RV2 really has to see if it was actually much larger than the York 210. I've heard "I think 12 cu-in" or "maybe 12.5 cu-in", but nobody seemed to know for sure. If the RV2 was really 12+in², I would've considered it instead of the York, but since they are virtually the same I will stick with the more common, less expensive, and easier-to-mount York. As we all know, the old systems using these compressors (and the GM A6 and R4) cooled ridiculously well. Displacement is part of the reason, but many "modern" compressors like the Sanden 510, Seltec TM-16, and Denso 10PA17 have similar displacement to the RV2 and York. Despite that, they don't cool as well at low speed, even if using the same system components, oil, and refrigerant.
I have a Seltec TM-16HS that I drained the PAG oil from and have completely flushed with Suniso 3GS mineral oil to remove all the PAG oil residue in order to be able to use it with R-12. However, after some careful research I have concluded that the old 2-cylinder recips actually have advantages over the "modern" axial compressors that everyone tries to convince you to retrofit in their place. My background is stationary refrigeration, so consider this: manufacturers of stationary reciprocating compressors, whether hermetic or semi-hermetic, use designs basically identical to the RV2 or York. Efficiency is THE major issue with stationary compressors, so any design that increases efficiency would be used over one that is less efficient, even if it increased cost or complexity. That is why scrolls are now the main compressor technology above 2 to 2-½ tons. However, below that range 1 and 2 cylinder recips with efficient valve plates are still the rule. No stationary compressor manufacturer has ever produces a swash plate or wobble plate compressor with multiple small cylinders. Turns out there are several good reasons why. Where ruggedness and longevity are more important than the last iota of efficiency, semi-hermetics of 2 to 25 tons or more are still very common. Semi-hermetic recips are crank-rod-piston designs with relatively few, large, long-stroke cylinders rather than swash or wobble plates driving many smaller cylinders. Again, for good reasons.