Thickness of those end gaskets may figure in to rotor end clearances. Sullair screw machines adjust end clearances via gasket thickness, too thick and a small machine hurts in efficiency, too thin and interference causes heat, bigtime. Sullair sells especially formulated lube oil (24KT lube) for screw type compressors, about a thousand bucks per five gallon pail, contains glycol. At one time the lube was required along with scheduled maintenance to allow a 24 month warranty on the air end. Wrong lube oil, too much heat and the oil/air separator would combust to ash.
YMMV
YMMV
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