Narrative:

En route from chicago meigs (cgx) to danville, il, at 5,000 ft 20 mins into flight, right engine began surging. Very cold outside (-10 degrees F). Thought propeller oil was congealing, so I exercised propeller at 200 RPM. Manifold pressure also began fluctuating. Temperatures looked normal but oil was visible on top right engine cowl. Oil pressure began dropping and engine got rough. As a precautionary measure, knowing I was close to kankakee airport, I feathered right engine and declared an emergency just in case there were delays. Center cleared me to 2700 ft and was giving me distance to airport. I saw airport and landed uneventfully. Still with chicago center, taxiing in, I canceled IFR. I am not sure yet what went wrong with engine. It flew fine 2 days prior, but today it was very cold and I think something froze or malfunctioned due to extreme temperature. My decision to declare an emergency was not out of fear or mixed feelings. I needed to get down on the ground without delay and prompt assertiveness. I heard no other traffic in my area or kankakee airport, and the controller was not very busy, probably because it was so cold. I believe that my 2 full yrs of previous employment as solely that of multi engine instrument inspector, and my knowledge of pilot/controller responsibility in an emergency situation, led me to the safe and uneventful task of getting a distressed aircraft on the ground. Callback conversation with reporter revealed the following information: reporter revealed that the post-flight inspection and engine tear down revealed a hole in the #1 piston. The inspecting mechanic said the #1 cylinder had been run too lean and that 1 of the 2 fuel injection nozzles could have frozen up due to the cylinder's location in the front engine and the severe cold temperatures in chicago that day. The engine simply pumped the oil out through #1 cylinder. The draw back on this aircraft was that the cylinder head temperature gauge only registers off of 1 cylinder and it wasn't the front one, #1 cylinder. The engine had been rebuilt and just now re-installed on aircraft.

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Original NASA ASRS Text

Title: INFLT ENG SHUTDOWN. EMER DECLARED WITH DIVERSION TO ALTERNATE ARPT.

Narrative: ENRTE FROM CHICAGO MEIGS (CGX) TO DANVILLE, IL, AT 5,000 FT 20 MINS INTO FLT, R ENG BEGAN SURGING. VERY COLD OUTSIDE (-10 DEGS F). THOUGHT PROP OIL WAS CONGEALING, SO I EXERCISED PROP AT 200 RPM. MANIFOLD PRESSURE ALSO BEGAN FLUCTUATING. TEMPS LOOKED NORMAL BUT OIL WAS VISIBLE ON TOP R ENG COWL. OIL PRESSURE BEGAN DROPPING AND ENG GOT ROUGH. AS A PRECAUTIONARY MEASURE, KNOWING I WAS CLOSE TO KANKAKEE ARPT, I FEATHERED R ENG AND DECLARED AN EMER JUST IN CASE THERE WERE DELAYS. CTR CLRED ME TO 2700 FT AND WAS GIVING ME DISTANCE TO ARPT. I SAW ARPT AND LANDED UNEVENTFULLY. STILL WITH CHICAGO CTR, TAXIING IN, I CANCELED IFR. I AM NOT SURE YET WHAT WENT WRONG WITH ENG. IT FLEW FINE 2 DAYS PRIOR, BUT TODAY IT WAS VERY COLD AND I THINK SOMETHING FROZE OR MALFUNCTIONED DUE TO EXTREME TEMP. MY DECISION TO DECLARE AN EMER WAS NOT OUT OF FEAR OR MIXED FEELINGS. I NEEDED TO GET DOWN ON THE GND WITHOUT DELAY AND PROMPT ASSERTIVENESS. I HEARD NO OTHER TFC IN MY AREA OR KANKAKEE ARPT, AND THE CTLR WAS NOT VERY BUSY, PROBABLY BECAUSE IT WAS SO COLD. I BELIEVE THAT MY 2 FULL YRS OF PREVIOUS EMPLOYMENT AS SOLELY THAT OF MULTI ENG INST INSPECTOR, AND MY KNOWLEDGE OF PLT/CTLR RESPONSIBILITY IN AN EMER SIT, LED ME TO THE SAFE AND UNEVENTFUL TASK OF GETTING A DISTRESSED ACFT ON THE GND. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR REVEALED THAT THE POST-FLT INSPECTION AND ENG TEAR DOWN REVEALED A HOLE IN THE #1 PISTON. THE INSPECTING MECH SAID THE #1 CYLINDER HAD BEEN RUN TOO LEAN AND THAT 1 OF THE 2 FUEL INJECTION NOZZLES COULD HAVE FROZEN UP DUE TO THE CYLINDER'S LOCATION IN THE FRONT ENG AND THE SEVERE COLD TEMPS IN CHICAGO THAT DAY. THE ENG SIMPLY PUMPED THE OIL OUT THROUGH #1 CYLINDER. THE DRAW BACK ON THIS ACFT WAS THAT THE CYLINDER HEAD TEMP GAUGE ONLY REGISTERS OFF OF 1 CYLINDER AND IT WASN'T THE FRONT ONE, #1 CYLINDER. THE ENG HAD BEEN REBUILT AND JUST NOW RE-INSTALLED ON ACFT.

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.