Narrative:

After having extensive avionics work, and engine monitor installed, I test flew the aircraft. All was ok. It was evening so I elected to fly home the next morning. About 50 mi from the departure airport (T82) I smelled smoke. Engine instruments were ok. I noticed a black hole on the inboard side of the left engine. I secured the engine, and the smoke smell stopped. Grey approach was notified of the situation and they vectored me to burnet (bmq). Landing was uneventful. Logs for the work were being overnight mailed.

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Original NASA ASRS Text

Title: A C340A SINGLE PLT, ON HIS FIRST POST MAINT FLT, EXPERIENCED ENG TROUBLE AND DIVERTED TO BMQ FOR AN UNEVENTFUL LNDG.

Narrative: AFTER HAVING EXTENSIVE AVIONICS WORK, AND ENG MONITOR INSTALLED, I TEST FLEW THE ACFT. ALL WAS OK. IT WAS EVENING SO I ELECTED TO FLY HOME THE NEXT MORNING. ABOUT 50 MI FROM THE DEP ARPT (T82) I SMELLED SMOKE. ENG INSTS WERE OK. I NOTICED A BLACK HOLE ON THE INBOARD SIDE OF THE L ENG. I SECURED THE ENG, AND THE SMOKE SMELL STOPPED. GREY APCH WAS NOTIFIED OF THE SIT AND THEY VECTORED ME TO BURNET (BMQ). LNDG WAS UNEVENTFUL. LOGS FOR THE WORK WERE BEING OVERNIGHT MAILED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.