Iv'e seen this happen before one or twice. About the only way the gauge will loose glycerin is if you cut the nipple off the rubber plug on top of the gauge. Then the gauge usually has to be mounted at an angle for the liquid to slowly drip out. Make sure the gauge is mounted vertical. I usually suggest a pin hole be pushed through the rubber plug instead of cutting off the tip/nipple on top of the gauge as suggested by the manufacturer. The manufacturer is McDaniel Controls if you want to contact customer service to know what fluid is in the gauge (model J6B). The info page says glycerin is in the gauge.
http://www.mcdanielcontrols.com/
http://www.mcdanielcontrols.com/pdf_files/BRO_GRAY1015.PDF

Last edited by Bill Cody; 04/25/16 07:17 PM.
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