Refurbishing a neglected cornelius keg

[ReeseAllen]

I received a pin-lock corny keg from a friend recently. He'd had it in his garage for years. It was never properly cleaned after its last use, so it was filthy inside and out, and had lots of rust spots. Most people seem to think that stainless doesn't rust. It does. It's rust-resistant, but not rust-proof. Fortunately, the rust was limited to the posts, the fittings, and a few small spots around the top and the inside near the top.

Today, I went to the hardware store to get a wire brush and some naval jelly. Naval jelly is a bright pink substance that has the same consistency as mucus. It turns rust (iron oxide) into ferric phosphate, which can then be brushed off easily leaving a pristine steel surface.

Here are some shots of the inside of one of the fittings after I removed it. It's damn near rusted shut, and the threads are very corroded. The other one wasn't quite as bad.



There was a bit of corrosion on the top around the lip of the main opening, so it got a slathering of naval jelly. I also filled both fittings with the jelly and then threaded them loosely onto the posts for the first soak.



After letting it soak for about 15 minutes, I took the wire brush to the corroded areas. I had to repeat the soak-and-scour on the posts three or four times. As you can see in the photo below, the posts came out nearly spotless. You can also see a blob of naval jelly inside the keg which is taking care of some small rust spots I discovered in there.



The fittings and the gas dip tube needed to be filled with naval jelly, soaked, and then rinsed and wire-brushed three or four times. I managed to use a wooden dowel to get the jelly into the liquid dip tube, although I wasn't able to scrub the inside.



The photo below is the fittings and dip tubes after cleaning. Also pictured is the O-ring replacement kit I got from my LHBS. Keg lube is necessary for the o-rings, which isn't pictured.



The fittings came out looking pretty good. The left fitting was the worse of the two at the beginning. Both still have a bit of corrosion I couldn't get out, but compared to the way they looked when I started, they look pretty damn good.



I've now cleaned and sanitized the keg and all its components. Now I just need to see if it'll hold pressure properly and then rack some beer into it...

 

[ReeseAllen]

I forgot to mention: the hardest spots to take care of were inside the keg, around the posts. I have a little lighted dental mirror thing that I can use to look at them, so I could see whether it was clean yet, but most folks have to go by feel. They were VERY rusty. I had to spend a long time scrubbing with the wire brush and the naval jelly to clean them up.

 

[ReeseAllen]

To pressure-test it, I let the keg and the CO2 tank sit out and get to room temp overnight, then filled the keg to 10 psi with CO2 and disconnected it. When I checked it about 4 hours later, it was still at 10 psi. I think I'll probably just leave it overnight and check it again tomorrow after work. If it's still at 10 psi, then the porter I'm cold-crashing now will go into it.

 

[david_42]

Those dental mirrors with lights are handy. They can even be used to check your teeth!

Stainless steel has one really odd corrosion mode where you get pinholes between the grains. It can look fine, but weep constantly.

 

[TheCHICompany]

NEVER use bleach on any stainless!

 

[ReeseAllen]

The keg is now full of porter and carbonating in the fridge.

NEVER use bleach on any stainless!

Are you guys getting more ball lock kegs in stock anytime?