Please help me understand the compressor/oil in my 1970 OTS

I’m slightly to fully confused about the a/c compressor oil. I have come to the conclusion that the oil in the crankcase of the compressor is seperate from the oil that should be in the freon. (I opened the oil plug and I still have a vacuum) I’m I correct on this? If this is case my compressor is mounted horizontally and not sure how I check the level. The manual states checking the height of oil with a handmade oil stick. Is the height the same with horizontal vs vertical. And what modern oil should I use? And if my assumptions are correct, do I add any oil with the freon?

Please type slowly so I can understand!!!

I’ll answer because I can’t type any way but slow.

Yes, you aim for the same oil level, except IIRC only one of the two plugs (the one at the top) is used for horizontal mount. The level varies with the model (there is info on the internet) but it’s about one inch. The oil you want (if using the original R12) is 525 SAE viscosity mineral oil, available from Amazon and similar. You can also buy a dipstick (at least you used to be able to) instead of making your own.

I don’t think you need to add oil to the Freon unless you disturb other components in the system. For example, quite a bit resides in the condenser.

M bubble was burst anyways. I was pulling a vacuum with the valves at the compressor closed. Once I figured out they needed to be open, I found I had a big leak somewhere. Probably the evaporator

can you verify I am troubleshooting this leak correctly. I believe the leak is the compressor. I capped both valves/actually took both off and checked for leaks and both passed. So I believe the leak is in the compressor. I put air pressure into the valves connected to the compressor and squirted soapy water all over the compressor. NO bubbles. Where else could the compressor leak?

I’m far from eggspert when it comes to York/Tecumseh compressors. That said, I believe that the most common source of leaks is the shaft seal. This is behind the clutch, so you might be missing the bubbles. Perhaps remove the clutch–you’ll have to anyway to replace the seal if that’s it.

Lots in the archives of this site and the web in general. These compressors were ubiquitous in their day, BTW, if you’re not interested in Concours originality, there is a bolt on plate that allows you to substitute a modern Sanden compressor for the York.

And how right you are! That would make itself known by the spray of oil that it would put up under the hood and the front of the engine.

can you guys double check my troubleshooting/logic on finding leaks (I know I have more than one)

I removed both valves at compressor and plugged the compressor side and capped the hose side. Both valves did not leak (I did vacuum test and air test). Then with them both capped still to the hose side I connected back to compressor with new o-rings (the old ones were super stiff). Does not hold a vacuum and soapy water on fittings have no bubbles when charged with compressed air. I conclude that the compressor is leaking. Is this a correct assumption?
Next I plugged the fitting at the dryer that is coming from the condenser and removed the compressor fitting going to condenser/plugged the compressor side. No leaks. I am concluding that the condenser and lines going to/from are good? Correct?

I am doing the same with evaporator side but I have not gotten results yet. I’m I approaching this correctly?

@goffs did you read this post?

Yes. I believe I have a leak at seal plus some others