Thanks for the feedback on the video!
John L. - It's hard to know what happened first; sort of the chicken or egg syndrome. There is also the mystery of the darkened oil. That didn't smell burned but it had some odor in it. Makes me wonder if the lubrication properties of the oil were degraded. Note that I had changed the oil and run the compressor before the teardown, so what you saw in the video was new oil. The original oil looked like used engine oil; very dark brown.
Running with air in the system will of course oxidize the oil. The owner of the fridge this came from did tell me it worked before he put it in storage, and then wouldn't work afterwards. I don't think he ran it long after taking it out of storage. He may have been mistaken, in that it wasn't cooling even when he first obtained it. It was in a travel trailer which he has gutted for restoration, put all the things in storage, and is now reassembling it. That's when he found the fridge not working.
I've encountered 5 bad 1/8 HP Meter Miser compressors in my days of doing this work.
The first one was a burnout where the wiring insulation had crumbled and grounded out. Someone had put a 3-wire grounded cord in place, without paying attention to polarity. This caused the overload to be bypassed via the ground fault. That left current on the start winding at all times, whether or not the fridge was even turned on. That lead to an open circuit start winding on that one. I did cut it open but the entire inside of it was wrecked from corrosion due to the burnout. Rotor was rusted into the stator and couldn't pull out. This had apparently happened many years before I obtained that fridge and it sat for years with the burnout residue inside it. I didn't save that one and it was before my YouTube days.
The next failed one had an improperly installed, massively oversize hard-start kit which burned the winding out. It was something for a central A/C unit - not even close to correct but someone did guesswork and paid the price. The parts were new and I am pretty sure they did it themselves. They denied having done it themselves it and opted not to fix it; wanting me to leave it all as it was so they had "evidence to deal with" whoever did it LOL!
The next one was a burnout due to welded contacts in a Frigidaire YT-Relay. Again customer didn't want to fix it.
The one previous to the one in this video was seized up and no amount of voltage or heating up the housing would free it. Then I found an icepick hole in the evaporator. Apparently they had run it with an open hole in the low side until it took in as much air as it could take in, and destroyed the compressor. Owner opted not to fix this one.
My reasoning for typing out all that is this.... all of those failures aside from this most recent ones were clearly attributable to external causes damaging the compressor. Either electrical faults, or running with punctured system. This one might have been damaged from running too long with the condenser broken; however unless the owner is mistaken - that didn't happen.
I do have a theory, however. This is the final version of the Meter-Miser, which had no precooler on it. The compressor discharge goes directly into the motor housing without going through the precooler as it does on the earlier designs. I don't know what Frigidaire did differently in this compressor which lead them to believe it was OK to run this way, whereas the earlier ones they considered needing a precooler. The oil could have been overheated chronically over the years, leading to a lubrication breakdown. Or; or the fact that the compressor discharge is happening underneath the oil level could have lead to aeration or foaming of the oil. The precooler models have a chance for the oil to separate from the gas and return to the sump without as much turbulence.
As for the slow rotation of the rotor ring, Frigidaire did explain that in some historical literature. It is one of their patented design elements in the Meter-Miser. They allow the rotor to freely turn to minimize wear. This minimizes the speed of the sliding friction around the circumference of the rotor, where it interfaces with the bore of the housing, as opposed to spinning at motor speed. It should prevent uneven wear around the rotor, by keeping any one area from being in contact with the sliding vane too long; as opposed to a non-turning element. Apparently in this compressor, something established an abnormal wear point and it got stuck in that one area and caused the wear found. Could have been some small bit of contamination which got embedded in the parts; who knows. It seems that once it established a wear point, it was able to get stuck there under normal operating conditions and defeat the slow spinning rotor design.
Sincerely,
David
