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G.E. dielektrol capacitor making popping sounds internally

I recently acquired a G.E. 40,000 volt capacitor and initially it was fine but it has started making loud popping sounds inside while charging and discharging. It sounds like there might be arcing inside but it still holds a charge just fine which is quite strange. The sound always comes from the same exact spot and the capacitance has decreased from 1.88 uf to 1.5 uf. I'm wondering if inside the cap there is several smaller ones and maybe a connection came loose during shipping but I really don't want to pull it apart because it's welded shut. Any advice on what I should do would be helpful :) Thank in advance!

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It could be going bad, if it works it works, though it may eventually fail, which might be a problem if the circuit depends on it.

It could also be something about the packaging but considering the capacitance has changed that's less likely.
Ok thanks, what's the risk of it exploding considering it's quite a large cap?
Not wildly big, does it get hot during operation?
It hasn't at this point but I've only charged it up to 3 kv DC and discharged it through some aluminum foil. My biggest fear it that it's arcing inside and that it could blow up considering at full power it's over a kilojoule of energy. I'm not planning to use it with AC at all, only for DC applications, specifically a can crusher, coil gun, possibly an electro thermal gun and blowing up fruit.
You'll not know till you charge it up to full power, it also depends on how quickly it's being charged and discharged. If you're genuinely worried about it then fully charge it outside or somewhere else safe a good few times until you're sure. Check the capacitance afterwards, if it's stable it may have been a one time issue.
Ok I'll put a bigger resistor on the charging system and charge it up as much as I can and see what happens. Also I just noticed this but sometimes within 45 seconds after it's been fully discharged and even when the terminals are shorted it will pop inside sometimes and one of the times when the terminals weren't shorted it made a small spark when I shorted them.
The bigger resistor did the trick!!!! Thanks for everything :D :D