co2 leak?

If you do take the needle valve off, its going to take some force.Normally they use a sealant around the screwed in areas and only when they get unscrewed do they normally leak.Did the previous owner do this?
I don't know.. I don't know anything about him or this tank, other than it was $100 from craigslist, and I already had this thing off in my hand, there are 2 little black rubber seals inside that "look" ok but it does slide in and out really easy.. I'll take pictures
 
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