I inherited a broken weedeater from my father-in-law. The string is stuck inside the machine so you cannot pull the cord. He took it to Sears (it is a craftsmen, gas powered bushwacker)to fix and they said it needed a new piston, gasket and I think it says cylinder on the repair ticket. They wanted $109 to fix it. He gave it to me instead. I need a weedeater. Can I fix it myself and is it worth the cost?