testing keg pressure

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Well-Known Member
Oct 7, 2007
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Let me preface by saying, first time experience here with this be kind.

So I've purchased some used kegs around the holidays. Over 7 days shipping to get to CA from NY. Why not purchase them closer....because they were 3 gallon kegs at killer price (~$50 per including shipping). The were filled with pressure before shipping. When they arrived, I pulled up on the relief valve slightly to hear the release of pressure.

This brings me to my question. Is there any way of checking to see how much pressure is in them. Could I hook up the gas in to the keg and them attach it to the regulator? I keep thinking this won't do it because it's only measuring the output to the keg right?
I'm concerned to know whether or not they hold pressure correctly. I suppose if there is a tiny leak, I might be able to address them empty instead of after being filled with beer.
I'm also wondering about this. I'll rig up some sort of cheap pressure gauge, maybe post pics later.
Drain them down, throw 5psi or so in there off your reg and let them sit for a while ( a few days should do). If there is still pressure, odds are you're good to go.

Honestly, it doesn't much matter. If they had pressure when they were shipped, they CAN hold pressure. You may need to replace the rubber after you open it up, but at least you know that there are no structural problems. Replacing/lubing the rubber should be part of regular maintenance.
I got 8 kegs a while back, to test, I ran a hose off the gas out fitting, and whittled down an tire valve stem, stuck it in the hose, and used a tire gauge, however, I was measuring about 40 psi, and that would not be accurate, as a keg that seals at 40 may not at 12.
Be careful of temp changes because it will throw off the reading and give you a false sense of leakage. Just put a half gallon of water in, seal it, hit it with 10psi and invert the keg over a paper towel. If it's going to leak, it will leak water.
Take a spare gas tap, hook up a short rubber hose, and attach a 100psi pressure gauge to it. Fill the tank with ~50 psi and leave it for a week.

If the keg held pressure when you picked it up, chances are it will continue to do so. Regardless, any new keg I get gets torn down and all of the gaskets get replaced. Most of them will be dry rotted, cut, or stink like soda. Clean the posts, cut the beer tube a little if you wish, lube it up and slap it back together