Free stuck piston rings with Sea Foam [SOLVED]

Yes, it is safe to add Sea Foam through a spark plug hole. Mechanics have used this method for decades to free stuck rings and clogged expander rings. How to do it:  Remove the spark plugs and pour Sea Foam into each cylinder cavity through the plug hole. [Note that it’s easier to use Sea Foam Spray.]  Let the engine sit and soak up to 3 days (if you have the time). Be sure to crank the engine once a day to loosen the rings. You can also add a little more Sea Foam to each cylinder each day as it sits. Adding Sea Foam to the crankcase oil helps, too!