Jun air compressor

Hey gang!

Wondering if anyone has an older Jun Air compressor that they have
worked on? I have an old model 12-50 with two #6 motors. One of the
motors started blowing smoke out the vent tube and it smelled like
plastic. I immediately shut it down, changed the oil on both, let it
sit overnight and started again in the morning with the same results.
The smoking motor also is not building the suction the other is. Just
by placing a finger of the vent tube.

Everything looks good inside, no debris or anything loose of floppy.
I have not pulled the heads as I am looking for an idea as to what
might be wrong and how to take it apart first, rather than taking it
apart and breaking something else. Been there.

Thanks for any tips.

Note From Ganoksin Staff:
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