Narrative:

The flight was made from mqj in VFR conditions en route to 08C. 08C was IFR but was forecast to clear at our ETA. 30 mins out of mqj we leveled off at 5500 ft MSL above a broken layer of clouds. Approximately 10 mins later the engine started to shake and lose power. I was the safety pilot in the right seat. As I checked the mixture and propeller control and found no problem, the PF, in left seat, reduced power and descended through a hole in the broken layer. By this time I had found okk 109.8 330 degrees to at 5 NM on the LORAN. We landed without incident and asked the local mechanic to check the engine. He found #4 cylinder to have 0 compression with approximately 1 1/2 inch crack just to the inside of the fuel injector nozzle.

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Original NASA ASRS Text

Title: PRECAUTIONARY LNDG MADE IN DIVERSION TO ALTERNATE ARPT WHEN AN ACFT EQUIP PROB BECOMES EVIDENT.

Narrative: THE FLT WAS MADE FROM MQJ IN VFR CONDITIONS ENRTE TO 08C. 08C WAS IFR BUT WAS FORECAST TO CLR AT OUR ETA. 30 MINS OUT OF MQJ WE LEVELED OFF AT 5500 FT MSL ABOVE A BROKEN LAYER OF CLOUDS. APPROX 10 MINS LATER THE ENG STARTED TO SHAKE AND LOSE PWR. I WAS THE SAFETY PLT IN THE R SEAT. AS I CHKED THE MIXTURE AND PROP CTL AND FOUND NO PROB, THE PF, IN L SEAT, REDUCED PWR AND DSNDED THROUGH A HOLE IN THE BROKEN LAYER. BY THIS TIME I HAD FOUND OKK 109.8 330 DEGS TO AT 5 NM ON THE LORAN. WE LANDED WITHOUT INCIDENT AND ASKED THE LCL MECH TO CHK THE ENG. HE FOUND #4 CYLINDER TO HAVE 0 COMPRESSION WITH APPROX 1 1/2 INCH CRACK JUST TO THE INSIDE OF THE FUEL INJECTOR NOZZLE.

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.