Narrative:

7 mi northeast of the south bend VOR, I encountered roughness in the left engine so I decided to land right away. I did not declare an emergency. Meanwhile, oil started coming out of the right side of the engine. I looked at the instruments, but there was nothing to indicate any malfunction. Everything was normal. I reduced the left engine power to idle. By that time, I had been cleared for the ILS approach. The landing was performed without incident, however, emergency crews were waiting for us and followed us to the ramp. The firemen requested to see my license and medical, and I presented them with these documents. They also got the name and address of the aircraft owner. The tower contacted crash fire rescue equipment by radio and asked them to have me call the tower, which I also did. As soon as I called the tower, the FAA personnel came in. The FAA did the equivalent of a ramp check on me, asking to see my licenses, aircraft papers and logbooks. They also asked the mechanic to submit a written opinion as to the cause of the malfunction. Although I reported to the tower that I was having trouble with the left engine and that I had an oil leak, I would like to repeat that I did not ask for priority handling or declare an emergency. The FAA personnel assured me that this was a routine follow-up, that it did not qualify as either an accident or incident, and that there would be no further investigation. Upon opening the engine cowling, the mechanic found that the #5 cylinder had a crack in it. The crack was under the push rod tube housing. Hot gases evidently heated and cut the push rod tube housing and heated the push rod itself, softening it. As it became soft, it collapsed. Oil was allowed to overflow through the crack in the push rod tube housing.

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Original NASA ASRS Text

Title: SMT HAD OIL LEAK AND ROUGH RUNNING ENGINE, MADE SOFT LNDG, BUT UNHAPPY ABOUT EMERGENCY EQUIPMENT BEING ALERTED.

Narrative: 7 MI NE OF THE SOUTH BEND VOR, I ENCOUNTERED ROUGHNESS IN THE LEFT ENGINE SO I DECIDED TO LAND RIGHT AWAY. I DID NOT DECLARE AN EMER. MEANWHILE, OIL STARTED COMING OUT OF THE RIGHT SIDE OF THE ENGINE. I LOOKED AT THE INSTRUMENTS, BUT THERE WAS NOTHING TO INDICATE ANY MALFUNCTION. EVERYTHING WAS NORMAL. I REDUCED THE LEFT ENGINE POWER TO IDLE. BY THAT TIME, I HAD BEEN CLRED FOR THE ILS APCH. THE LNDG WAS PERFORMED WITHOUT INCIDENT, HOWEVER, EMER CREWS WERE WAITING FOR US AND FOLLOWED US TO THE RAMP. THE FIREMEN REQUESTED TO SEE MY LICENSE AND MEDICAL, AND I PRESENTED THEM WITH THESE DOCUMENTS. THEY ALSO GOT THE NAME AND ADDRESS OF THE ACFT OWNER. THE TWR CONTACTED CFR BY RADIO AND ASKED THEM TO HAVE ME CALL THE TWR, WHICH I ALSO DID. AS SOON AS I CALLED THE TWR, THE FAA PERSONNEL CAME IN. THE FAA DID THE EQUIVALENT OF A RAMP CHECK ON ME, ASKING TO SEE MY LICENSES, ACFT PAPERS AND LOGBOOKS. THEY ALSO ASKED THE MECHANIC TO SUBMIT A WRITTEN OPINION AS TO THE CAUSE OF THE MALFUNCTION. ALTHOUGH I REPORTED TO THE TWR THAT I WAS HAVING TROUBLE WITH THE LEFT ENGINE AND THAT I HAD AN OIL LEAK, I WOULD LIKE TO REPEAT THAT I DID NOT ASK FOR PRIORITY HANDLING OR DECLARE AN EMER. THE FAA PERSONNEL ASSURED ME THAT THIS WAS A ROUTINE FOLLOW-UP, THAT IT DID NOT QUALIFY AS EITHER AN ACCIDENT OR INCIDENT, AND THAT THERE WOULD BE NO FURTHER INVESTIGATION. UPON OPENING THE ENGINE COWLING, THE MECHANIC FOUND THAT THE #5 CYLINDER HAD A CRACK IN IT. THE CRACK WAS UNDER THE PUSH ROD TUBE HOUSING. HOT GASES EVIDENTLY HEATED AND CUT THE PUSH ROD TUBE HOUSING AND HEATED THE PUSH ROD ITSELF, SOFTENING IT. AS IT BECAME SOFT, IT COLLAPSED. OIL WAS ALLOWED TO OVERFLOW THROUGH THE CRACK IN THE PUSH ROD TUBE HOUSING.

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.