Stupid question about glycerin filled tank gauge...

Hello AGN:

This might be a stupid question and I THINK I know the answer to it but wanted to ask before doing anything stupid...

A couple of months ago, I noticed a clear, sticky fluid on my floor under one of my SCBA tanks. Turns out, the little black plug on the top of the gauge popped off and all of the glycerin from the gauge leaked out onto the floor. I know the glycerin is in there to dampen the vibration of the gauge needle and whatever but it is still OK to use that tank to fill my guns as normal without the glycerin in the gauge face, right? I would think so but wanted to make sure.

Oh, and follow-up question: can I just refill it with glycerin (or some other alternative) and put the cap back on???

Here's the gauge and where opening where the glycerin came out of:
tank gauge.jpg
 
Glycerin is used as a buffer.
For static pressures ie tanks it not needed.
For compressors whare actual pressure flucturates, glycerin is needed to stabilise mechanical vibrations.
The pressure gauge is actuated by a copper spiral and that work hardens with vibration. To avoid this, glycerin is introduced as a vibration dampener in the pressure gauge itself.

Clear as mud or do you need further explanation?
 
Had a cheap gauge do the same thing. My issue was that the fittings inside the gauge had a very small leak. This allowed air pressure to build just behind the gauges glass window. After enough pressure built up the plug blasted off across the room shooting glycerin across the room as well. The gauge may be defective. If this happens again, I'd replace it.
 
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You have already received some excellent comments, of which I agree, having worked for a company that manufactured glycerine filled gauges and other components. Anyway, I googled refilling glycerine filled gauges. Several leads popped up but I linked what appears to be a good one from a leading manufacturer.


Randy
 
probably leaking internally, id replace it ..
Perhaps the OP can put a piece of tape over the fill hole and pressurize the system. If the tape pops off, it’s bourdon tube inside or solder joint has failed. But usually if the joint or tube fails there’s a whole lot of air rushing out.
 
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Yen, I've had gauges leak glycerin because the rubber plug wasn't seated correctly but also had the plug forced out by pressure. When the latter happened I replaced the gauge. Pressure SHOULD NOT be building in the gauge compartment (behind the "window") it should only be moving the needle & not get past the needle. (Pitot tube arrangement)
 
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Hello All,

I had typed a reply to the first couple of responses yesterday and THOUGHT I hit the "Post Reply" button but never did so it's just been sitting in my drafts ever since!

Thank you for all of the responses and everything you guys have said makes sense. I actually picked up some glycerin from the store yesterday and was going to refill the gauge because the plug can just be easily popped back in and the fit seems very snug. At the same time, the points made about pressure build-up in the gauge make sense and if there is an issue there with this gauge, it'll likely end up shooting the plug (and therefore glycerin) out again at some point in the future.

Ironically, of the four tanks I have, I've never liked the fill assembly & gauge on this particular tank due to its poor ergonomics. For my bday recently, I splurged for one of Donny's/Saber Tactical's fancy new gauges (which is totally overkill for its purpose) so I was going to install it on one of the tanks anyways. So it looks like I know which tank it's going on now :) I just have to use up the air in this tank and will then make the swap.

Thanks guys!
 
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