I picked up an Aircap Edger/Trimmer recently at a garage sale. The engine runs but has low compression, so I am looking to replace the rings. The engine is a 2 cycle Tecumseh, looks to be around 30cc. The number on the engine label is 817/601/L158K4. I searched for that number but found nothing. Can anyone help me identify this engine so that I can rebuild it? I can provide more info or post pics if that would help. Thanks.