My friend got a corny keg for free and asked me to pressure test it. I put some starsan solution in it and pressurized it to 25psi then shook it. The pressure relief valve leaked as judged by soap bubbles coming out the metal holes in the lid where it screws in. I removed it, cleaned and inspected it and put it back on. When I recharged with gas it seemed to be OK but this morning the keg had no pressure. I’d poured out the Starsan so I don’t think it absorbed into the liquid. I’ve never had one of these valves fail on my own kegs. I suppose its just a weak spring and the thing needs to be replaced? Its the type with the gray plastic body.
That’s entirely possible. You can try adding some keg lube to it and see if that helps it seal. It’s also possible it is leaking from somewhere else. I would do the keg lube, seal it up, pressurize to 20 psi, disconnect the gas and spray the top with starsan and see if it’s leaking. If there are no obvious leaks let it sit overnight and check it again. You might need to replace the PRV, you can buy them online.
Here’s a good price, although the shipping will kill you. I’m sure most online beer stores sell them, you can roll it into your next order and save that way.
http://stores.kegconnection.com/Detail.bok?no=239
I’ve got one that’s on it’s way out too. Maybe try adding a small gasket to the top of the threads before you screw it back on. I’ve also used teflon tape for a quick fix too. Definitely try to find a gasket or make one to fit. One of mine is real finnicky, if the top of the springs is moved ever so slightly it leaks…That’s why I’m only buying new kegs from now on. I hate leaks.
Or maybe it’s got some gunk in the spring, soak it in oxyclean and hot water and try it again before you buy the part. That’s what I’d do, otherwise, $8 aint bad for a keg.
I’ve had that happen before on a few occasions. Once I had part of a hop bag get stuck in the valve which was easily fixed. Another time the spring just wore out and I replaced it. I keep a couple on hand for this reason. They are fairly inexpensive and easy to replace.
I thought about trying keg lube, I guess that would tell me if it was leaking through the threads of the plastic body. I cleaned it so the problem isn’t foriegn matter. Not sure what a gasket would do unless the problem is the threads not sealing. I’ll see what I can do about that, I just assumed the spring was getting weak and the pressure was pushing it up.
I already scoped prices on ebay but since it isn’t mine I’m just going to pass the info on. Might buy one or two for myself, just for backups. I have everything but this item in my repair parts stash, go figure
I know the guy who gave him the keg so I asked him if he’d ever used it. He hadn’t so he didn’t know it wasn’t holding pressure. Its a nice looking keg too.
Our LHBS carries replacement relief valves so check local if you can. They even carry a universal valve that allows you to vent a Pin-lock keg.
Paul
I made another attempt to get this valve to seal. Cleaned the lid where the bottom of the valve seats, lubed this and the plastic threads and reinstalled very snugly. Still got the leaking through the holes which I believe means the bottom spring-loaded seal is not working. So I’ll report this to my friend and let him decide where to get the replacement PRV.
Just as a followup, I ordered a couple of replacement relief valves and installed a new one for my friend, works like a charm now.
Sweet, thanks for the update Lennie.
Ahh success. Sometimes it’s easier to just replace faulty parts. That’s my experience. 
I agree. I think the springs weaken, and there’s no practical way to test them, other than by their performance.
I’ve recently had to replace one. Ditto a few poppet valves, gas side, a sneaky leak source.
I have a similar problem. I bought a used keg with a leaky valve, replaced with new valve but still leaks. My thought is that it was the wrong valve installed in the first place. The kind I have/had is like the type A, and on most web sites, I see a type C…but is there a type B?..and how do I know what I need? I would hate to order a type C if i need something else.
thanks,
g
I’ve been offline for awhile, or I would have responded sooner.
Northern Brewer’s site has really helped me out. I have a lot of Super Champion kegs. I started switching to the Type B posts and poppets. I like them a lot. They work well. If you haven’t already, I would suggest checking out the printed side of your kegs, and discover which kind you have. Like a lot of guys, I bought my kegs used at the LHBS, knowing nothing about them when I started. Most of mine had Type A’s on them, and so I’ve slowly been switching them out. I’ve spent a little, but now my kegs are in pretty good shape. My LHBS has the Type B’s on hand for the same price as Northern Brewer. The Type C is a little different, the poppet is designed to stay in the post. I have one keg made for that. Hope that helps.