Narrative:

I lost an engine in an small transport en route from willow run, mi, (yip) to dupage, il, (dpa). The aircraft was VFR at 2500 ft on flight following. While 15 mi east of pullman VOR, the oil pressure was slightly lower than usual and the throttle was slightly more forward than usual, to keep the same manifold pressure I decided to go around lake michigan to the south. I asked for a vector direct benton harbor airport. I was the cleared off frequency to talk to my boss via benton harbor unicom. He said land at benton harbor. The engine was still running smooth, no oil was visible on the engine (daylight), cht and oil temperature were normal. I switched back to approach to find out that I was past benton harbor, and the closest airport was south bend. When the needle reached the bottom of the green arc on the oil pressure gauge, power was set to zero thrust (15 inches). 2 to 3 mi northeast of south bend at 2500 ft, the engine began running rough. I feathered it. Over the airport at 2500, I entered the pattern, lowered the gear, and landed. Having altitude, no cargo, 1/2 tanks of fuel, and good WX made the emergency go very well. I now believe I should have shut down the engine when it reached the lower limit on the oil pressure gauge. This would have prevented some damage to the engine. A gasket on the oil pump had blow, blowing oil out and under the engine. I landed with 2 quarts of oil with metal in it. A good safe landing with bad results to the engine. Believe the oil pressure gauge, very reliable.

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Original NASA ASRS Text

Title: SMT HAS ENG OIL PROBLEM. DIVERTS, PLANS PRECAUTIONARY LNDG. HAS TO FEATHER ENG WHEN OVER ARPT. EMER LNDG.

Narrative: I LOST AN ENG IN AN SMT ENRTE FROM WILLOW RUN, MI, (YIP) TO DUPAGE, IL, (DPA). THE ACFT WAS VFR AT 2500 FT ON FLT FOLLOWING. WHILE 15 MI E OF PULLMAN VOR, THE OIL PRESSURE WAS SLIGHTLY LOWER THAN USUAL AND THE THROTTLE WAS SLIGHTLY MORE FORWARD THAN USUAL, TO KEEP THE SAME MANIFOLD PRESSURE I DECIDED TO GAR LAKE MICHIGAN TO THE S. I ASKED FOR A VECTOR DIRECT BENTON HARBOR ARPT. I WAS THE CLRED OFF FREQ TO TALK TO MY BOSS VIA BENTON HARBOR UNICOM. HE SAID LAND AT BENTON HARBOR. THE ENG WAS STILL RUNNING SMOOTH, NO OIL WAS VISIBLE ON THE ENG (DAYLIGHT), CHT AND OIL TEMP WERE NORMAL. I SWITCHED BACK TO APCH TO FIND OUT THAT I WAS PAST BENTON HARBOR, AND THE CLOSEST ARPT WAS S BEND. WHEN THE NEEDLE REACHED THE BOTTOM OF THE GREEN ARC ON THE OIL PRESSURE GAUGE, PWR WAS SET TO ZERO THRUST (15 INCHES). 2 TO 3 MI NE OF S BEND AT 2500 FT, THE ENG BEGAN RUNNING ROUGH. I FEATHERED IT. OVER THE ARPT AT 2500, I ENTERED THE PATTERN, LOWERED THE GEAR, AND LANDED. HAVING ALT, NO CARGO, 1/2 TANKS OF FUEL, AND GOOD WX MADE THE EMER GO VERY WELL. I NOW BELIEVE I SHOULD HAVE SHUT DOWN THE ENG WHEN IT REACHED THE LOWER LIMIT ON THE OIL PRESSURE GAUGE. THIS WOULD HAVE PREVENTED SOME DAMAGE TO THE ENG. A GASKET ON THE OIL PUMP HAD BLOW, BLOWING OIL OUT AND UNDER THE ENG. I LANDED WITH 2 QUARTS OF OIL WITH METAL IN IT. A GOOD SAFE LNDG WITH BAD RESULTS TO THE ENG. BELIEVE THE OIL PRESSURE GAUGE, VERY RELIABLE.

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.