The posts themselves on the correct in and outputs would cause the CO2 and tap ball valves to fit properly?They are slightly different sizes, so the gas post does not fit a liquid disconnect easily. So the grey (gas) disconnect should fit the one with the cuts easily, and the black (liquid) disconnect should fit the smooth post easily. If they're not fitting the proper post easily try keg lube or some oil as euge suggests. I wouldn't use olive oil since it can go rancid over time, although it might not really matter. But I've got a bottle of mineral oil I would use if not for the keg lube. Btw, don't spring for fancy mineral oil sold for oiling your wooden kitchen utensils. Buy the stuff that is labeled as a laxative (at least in the US). It is the same stuff, but 1/3 the price.
By the way, how do you get those posts off your kegs?I use what I call a keg wrench. It's a Craftsmen ratcheting box wrench I got from Sears for ~$12. 11/16" on one end, 7/8" on the other. Some of my kegs have smaller fittings, some larger, this one wrench fits both size fittings. Plus, it ratchets! I actually have two, after I lost one for a year when I moved.
I have some kegs where the rubber top comes up high enough that it is hard to get the wrench on - is that the thin area to which you're referring? I use vice grips or robo-grips to get hose off, but I tend to get rid of them after a while. I'm spoiled by my keg wrench.
As for bizarre fitting, no eyed deer. Maybe with a pic the collective wisdom of the forums could figure it out.
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