I have a 2 year old Ryobi RY34440 String trimmer, 30cc. Last year worked fine, this year pull cord is so easy to pull it doesn't even turn engine over. Is is the spark plug?

Either the pull starter is not pulling or you are not getting compression. To check you need to check the spark plug is still snug. If so, remove the plug and put a drinking straw in the hole to touch the piston. Slowly pull the starter to see if the piston is moving. If the piston is moving and the plug was snug then you are losing compression somewhere, like a head gasket. If not moving then the problem most likely is in the starter, and disassembly required to investigate.

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