How to Prepare a Used Soda Syrup Keg for Brewery Use

by Dion Hollenbeck,

from Homebrew Digest #1865, October 24, 1995

There has been a lot of talk about prepping used soda kegs for use in homebrewing and several people have asked me for the writeup I have of how I do it, so I think it is worth posting. I have run this by John Palmer to ensure no cruelty to Stainless Steel is advocated. B-} While I may go overboard with my prep, when I am done, the kegs look very close to brand new (that is given that I do not select kegs with cracked rubber or dents to begin with).

How to prepare a used soda syrup keg for brewery use

  1. Rinse off outside with hot soapy water and a ScotchBrite pad.
  2. Hit any paper labels with a soft brass bristle brush to break up the surface and make them more liquid permeable. If any paper labels are on the rubber, finish them off down to the rubber with the brass brush. For labels on SS, see next step.
  3. Finish removing the paper labels with more hot soapy water and a ScotchBrite pad. Don't try to remove any label glue, that is later.
  4. Sun dry the keg.
  5. Scrape any plastic labels off the SS with a razor blade being careful to not scratch the SS. Also, scrape off any large deposits of glue.
  6. Remove any residual glue from the rubber and SS with a cloth and Goo-Gone or CitraSolve.
  7. Remove Goo-Gone or CitraSolve with a heavy duty household cleaner.
  8. Open and rinse the inside with hot water.
  9. Brush out the interior with a hot water solution of 1 TBS TSP per gallon of water and rinse with hot water. Use a nylon bristle brush.
  10. Disassemble, brush out the dip tubes and valve bodies with the TSP solution and rinse with hot water. Again, use a nylon bristle brush.
  11. If there are any rust spots on the SS, use an oxalic acid based cleaner such as Bar Keeper's Friend or Kleen-King and a Scotch Brite pad to remove the rust.
  12. Rinse everything thoroughly with hot water and let stand in the sun to dry.
  13. If you needed to use an oxalic acid cleaner, store the keg inside for a week or two to let the natural oxidaton layer reform on the SS.
  14. Wipe the rubber top and bottom with a pure silicone spray put on a cloth.
  15. Obtain new O-rings and re-assemble.
  16. Store with the valve bodies and lid loose and a plastic bag over the top of the keg to prevent dust from entering.