Cleaning a Mechanical Gauge

Oil on the dial is indicative of oil migration from the pumping system. Improper and/or inadequate traps or user error are to blame for this problem. Clean with an appropriate solvent for the type of grease found. Rinse and dry the gauge before reinstalling back onto the line. Methanol is a good final rinse as it dries quickly and cleanly. 

Most gauges are sealed to the outside world and thus should be unaffected by atmospheric changes. 

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