Automotive Air Conditioning Information Forum

A couple of questions concerning what I have found so far:

When I drained the old compressor…..not a drop of oil came out. The clutch disk spun freely and I could hear and feel that it was still pumping. Is that unusual to have no oil in the compressor?

I was curious how much oil was in the accumulator so I cut it open and it too had no oil in it and the desiccant bag when squeezed did not have much in it either. Is that unusual and what does that signify?

I got the new compressor installed on the truck along with the suction and discharge line. The two lines are not connected and still have the two caps on the two fittings. I only put 4.5 ounces of oil in it because I didn’t want to risk losing some, while getting the suction and discharge line manifold connected to the compressor, and therefore not having an accurate account of the amount of oil.

With this truck, the manifold has to be connected before the compressor is mounted because of the limited space to work in so I also had to be very careful not to get any debris on the manifold mounting area at the same time.

I also got the fan and radiator shroud back on and got the new condenser installed with the caps still on the two fittings.

kenlou wrote: Mon Jun 30, 2025 7:57 pm When I drained the old compressor…..not a drop of oil came out. The clutch disk spun freely and I could hear and feel that it was still pumping. Is that unusual to have no oil in the compressor?

It's not unusual. For lubrication, some compressors rely on oil that's carried continuously throughout the system by the refrigerant. On the other hand, some compressors retain some of the oil. It depends on the design.

Unfortunately, there's no dip-stick to gauge whether a system has the recommended amount of oil in it. The only way to tell is to start with a "dry" system and add the oil from there according to the manufacturer's specifications—either by adding it all to the compressor (if it will accept it) or by "oil balancing" the system, whereby a certain amount is added to each component.

kenlou wrote: Mon Jun 30, 2025 7:57 pm I was curious how much oil was in the accumulator so I cut it open and it too had no oil in it and the desiccant bag when squeezed did not have much in it either. Is that unusual and what does that signify?

The accumulator should have "some" oil at the bottom. Could be that the system was low on oil to begin with.