Here are the inner workings of a York compressor.
This first picture shows the problem I was going to have if I left this York compressor on my project and used it.
Yuck.... the thing was extremely dirty and had collected some rust from something. I found a score in one of the cylinder walls from a piece of debris. I found a York that had a clean inside. The clutch wasn't the same diameter, the outside looked bad and the head fittings were a bit different. I talked to Brad Kilby that owns onboardair.com and he had a rebuild kit for the compressor. The kit is basically gaskets and a few seals.
But, first to the inner workings.....
This picture shows the cylinder side of the valve assembly. I took one reed valve off and left one on. The reed valves on this side allow air to come into the cylinder and does not allow air to be discharged back up through the intake. The intake air is circulated through one side of the top of the case before going into the cylinder.
On the other side of this assembly there is another set of reed valves. These allow the compressed air to escape.
There is a metal rig on top of the reed valve. I supposed this stops the reed valve from opening up all the way thus, the air is compressed from not being allowed to free flow through the valve. Note here; the compressed air is circulated through the other side of the case top. There is no passages between each side of the case. BTW - Yes, that is blood on the head. that dang scrapper/razor blade got me. Be careful, the gaskets get cooked onto everything by the heat generated.
After everything was done, I got this:
I decided to use some different fittings on the head so I needed to clean up and reuse the head off the 'dirty' compressor, I need to repaint it now. I mounted the electro-magnet, clutch and bolted on the brackets, and it is done.
One reason for the page was to show that the valves on a York do not need any oiling. I can't imagine why they would except to help them seal a bit better.