Great video! Very thorough in explaining what to do for us that do not know how the A/C system even works. I feel very confident in trying to do myself now. Thank you!
Good call on pointing out to verify that the seals are in the hose connectors. There have been a lot of complaints recently about leaky systems, and the missing seals might be why
Technically, you use the red plug to fill the oil; the black plug in front is officially called an "Oil/Gas separator." It is designed to be not sealed and allows gas/fumes and overspilled oil to escape to prevent damaging the pump.
The oil goes in the same low-pressure port if you bought the refrigerant with added oil. For oil along, it would be risky to gauge how much you need because you won't know if any of the oil leaked out of the compressor or just refrigerant. My personal opinion is don't add any oil, unless your system was entirely rebuilt and had the oil drained when compressor was replaced/serviced.
