Originally Posted by Catmandu
I bought four cornies from this guy last summer, for $40 each. There was no damage (other than normal wear & tear) and he proved all held pressure. However, one of them had a mis-sized post. Both the inlet and outlet posts were the same size, so the normal ball lock connectors would not fit on one of them (can't remember which of the two is slightly bigger, but you get the point). Haven't had a need yet to use the fourth keg, so haven't resolved the situation ... but will likely just use two of the same color connectors and distinguish them in another fashion.
Yeah, he charges them with air to prove they hold pressure and are good. That can be quite deceiving if that's all you're looking at.
Now I tell anybody looking at corny's to depressurize them, remove the lid and look at the shape of the opening. If they are bent or warped at all. pick another. Even a mangled one will hold pressure if you try hard enough. Mine was literally 3/8 of an inch out of plane with the lid, but it was holding pressure when I picked it up.
Not to say that guy was deceitful... this could be true with anybody selling a corny.