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The best way to clean the lock/ignition cylinder is to remove it. However you can use some electrical contact cleaner to spray inside and flush out some of the dirt/gum/grime and then lubricate with a silicon lubricant.
I would avoid spraying anything such as a penetrating oil inside the cylinder since the oils have a tendency to gum up. The silicon is dry and will not.
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What brand and where can I get this?
CRC or Loctite brand both make these products and can be found at any auto parts store.
Brand is not as important as just using the right product.
Thank you so much-I hope this works. Happy New Year!!