Does this sound like broken piston rings?

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I have a large walk behind weed trimmer on wheels which is similar to the ones in the linked page below. Have had it for a long time. I can’t get it to start. I replaced the spark plug and air filter. The plug is the right gap as specified in the owner’s manual. The spark plug generates a reliable spark. I pulled the plug, connected the coil connector to the plug then grounded it to the cylinder and pulled the starter cord. The plug sparks just fine and consistently.

I removed the spark plug, sprayed ether directly into the chamber and put the plug back on, and all I can get from the mower is an occasional pop out the exhaust. I’ve done the same by spraying ether into the carb and get about the same result. The pull cord pulls with the same resistance it always has.

https://www.google.com/search?q=wheeled+weed+trimmer&espvd=2&source=lnms&tbm=shop&sa=X&ved=0ahUKEwjxwPvJmarNAhUOQFIKHSoADQsQ_AUICCgB&biw=960&bih=498#spd=10878342580971112337