I have a 142 chain saw. It sat around for a long time with old gas in it and would start but couldn't keep it running. Dumped the old gas and refueled with the Trufuel 50:1. Then it started and ran fine. Cut a tree/bush down with it and shut it off and now I can't get it to turn over when I try to pull the start cord. In fact, the cord acts like something is jammed so that I can't pull the cord out very far( about 6 inches) and it just won't pull out any farther. The chain spins just fine.