honestly I'm not sure how much trouble it's worth to summon old op vs just posting new op's problem details. Old op didn't provide a lot of relevant details. Old op's response when asked what type of coupling was "Per client the coupling is a "flexible coupling". He never resonsded to questions about mechanical (vs magnetic) centering. Never responded to questons about misalignment (alhough I don't tink that is the cause). He turned to citing other people's opinions "the motor mfg is blaming it on the compressor...The refinery team disagrees..." without providing any basis for their claims (like the specific details those teams were looking at and using to support their assertions).
All of this suggests to me the old op was probably just asking a question on behalf of someone else and was far removed removed from the actual machine, didn't seem particularly tuned into what were the relevant technical details, and may not have been informed of the resolution if there ever was one.
I'm not meaning to disrespect anyone (sorry if it came out that way), just to point out it seems more productive to simply post new op's information rather than focusing exclusively on piggybacking onto this one old post (an old post for which: we don't know if it is the same cause; we don't know if it was ever resolved; we don't know if old op was informed of such resolution)