Keg won't seal, but...

When I purchased it, it was sealed and pressurized. Now when I try to seal it I can feel the air escaping from around the lid. I haven't used it yet so nothing's really changed. I thought it might be the O-ring on the lid, but my other lids won't work either (whereas they do work on their own kegs). Is there something I'm missing on the keg itself that might not allow for the lid to seal properly?

Keg Lube should do the trick. You can get it at any of the major online brew suppliers, or most local shops will probably carry it as well.

Keg lube will help. It's also a good idea to replace the O rings in your kegs. They get stiff and misshapen over time. You can usually get O ring kits from the place that sold you the kegs. Does the area on the keg around where the lid seals look undamaged? Damage there or in the lid itself can cause it not to seal.

I don't think it's the ring because all three lids I have won't seal. The lid does not look damaged, but I don't know too much about kegs. Like I said, it was sealed when I got it, so I'm just confused on what might have changed.
I'll try some lube.

have you tried blasting it with 30psi??

Also, have you tried turning the lid around the other way? Some of my lids just do better turned around. Even after locking it down, you might need to un-latch it and re-seat it if it leaks.

Are you absolutely certain it is the lid? I had a similar experience (it felt like the air was coming from around the lid) and it ended up being that the small O-ring on the gas in post was missing.

I have tried turning the lid, using the other lids, reseating them. I have not tried blasting it yet though. But it's a pretty strong leak, I can just put my hand there and feel it. That's what bugs me the most about it.
I'm thinking I might just take it to the store and ask them.

Sometimes cornies will seal under high pressure but leak at normal operating pressure. If you bought it locally and it won't seal at 8 psi I'd take it back.

Keg lub may help by allowing the o-ring to move around and get into the right spot. But in and of it's self the keg lub won't seal anything.

is the lid back in thee same position. I mark mine with a few lines on one side so I don't reverse the lid when putting it back on

I've got a couple of kegs that require a bit of ritual to get them to seal. I have to pressurize them while holding the lid in place (but not clamped down), then grab the clamp and pull and torque it around a bit until it fully seats in a way that doesn't leak. Then I clamp it down.

I've learned to be somewhat weary of the "guaranteed to hold pressure" claim some sellers give. Mine came well pressurized, but I think a lot of the reason it sealed easily was due to the coke syrup still caked to the o-rings. It became more difficult to seal them once I cleaned them up.

I usually start replacing things after 6 fills. Poppets last a bit longer

http://www.northernbrewer.com/keg-repair-parts.html

Also... in addition to using keg lube on the actual o-ring, also run a thin layer on the inside lip of the keg where it will meet the o-ring. Works like a charm.

I have had great luck with the extra thick, softer lid o-rings you can buy from Williams Brewing.