Tutorial: How a Cornelius Keg is Reconditioned
Check your soda kegs for dents, punctures and inspect the rubber seals and replace if they show signs of wear.
Beer kegs get a lot of wear and tear over the years. Taking good care of kegs is of the utmost importance in making sure that they continue to serve you well. When a keg is performing poorly, it is a good idea to give it some basic maintenance that aids in its functionality. The keg is cleaned thoroughly, checked for dents and punctures, and the rubber seals are inspected and most often replaced. This is called re-conditioning the keg, and can be done at home or outsourced to keg re-conditioners.
Re-conditioning a Cornelius keg, aka the soda keg, is one of the easier tasks a home brewer can tackle. The hardest part is getting a hold of the correct O-rings to go with your keg. Fortunately, you can buy kits for re-conditioning your Corny kegs, or take your old worn out O-rings to your local hardware store to get replacements. Most of the small O-rings are available for 20 cents or so each; you can also find them in bulk from stores like http://www.mcmaster.com. The large rubber O-rings that hold the main seal are a little pricier, around $2 each. But if you treat them well and use spray keg lube, they should last a good, long time.
Disassemble the Beer Keg
The first thing to do, if you want to tackle re-conditioning a Cornelius keg, is to disassemble the keg. You are going to need a crecent wrench or ratchet and very deep sockets to get the liquid and gas valves off, and most Cornelius kegs are SAE or “standard”, most likely a 7/8” or 11/16”. Turn the valve counter clockwise to loosen the connection. Sometimes these two valves are threaded differently from one another. It is important to take note of this - as you re-assemble the keg later, you may cross thread the valves if you mix them up. After loosening each valve lift them up and out from the keg body and thoughouly clean and particulate that may be inside the long stainless vliquid dip tube.
Valve Removal Procedures
After removing the valves, you will find one hole contains a very short tube with an O-ring, and the other contains a much longer tube with an O-ring. The shorter one is called the gas plug, and the longer one is called the liquid dip tube. Looking inside the valve, you will find an item called a poppet valve. This is a plastic piece with a spring wound around it. The piece of the valve that his comes out of is called the plug. Sometimes the poppet valves will need to be replaced, so you should inspect them closely.
If you are re-conditioning a keg that has been used for soda, it is a good idea to replace all of the O-rings and the poppet valves. Also replace the large O-ring which holds the lid tight. These O-rings may host bacteria and other contaminants and flavors.
Make sure that all of the parts of the keg are clean and sanitized. You may have to leave the liquid dip tube and gas filler tube to soak overnight in hot water in order to get all of the gunk out of them, so be prepared to do so. After everything has been cleaned, look closely at the liquid dip tube and where the bottom of it rests over the bottom of the keg. Many home brewers cut a short amount of the tube off in order that no yeasty sediment comes us through the beer lines. Cutting off even ¼” can save you some hassle, as sediment from yeast can make your beer come out too foamy from your spigot or tap. If you choose to trim the end off of your liquid dip tube, you may have trouble with rust in the tube unless you treat it.
This covers all the bases on keg re-conditioning for Cornelius kegs (aka soda kegs).
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Published: December 2, 2010
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