Thanks everyone, but I think the engine was damaged when the plane was crashed. As I noted, I did not witness the crash but with the HSNV broke off it must have been a bad crash.

While visiting my field I had one of our local engine gurus check things out. He worked with the valves, replaced the plug, blew through the lines, checked the fuel flow, etc and still could not properly tune her - he did everyting WCB suggested.

The engine sounds great, it transitions great, and can run full throttle with no problems. However, at idle it dies after a few seconds unless you nurse it.

He thinks the problem may be that when the engine impacted the ground the shaft may have been pushed back some so there is a small air leak causing it to lean out. (I may not be quoting him word for word but you get the idea.)

Is the engine worth having checked out by the factory? Would it be money well spent or should I just get another engine? A new one is about $80.