Narrative:

On 2 previous flts I had had indications of dirt in a fuel injector. On the first flight the situation corrected itself prior to the next takeoff. On the second flight the situation was corrected in-flight by reducing the mixture richness, then rapidly increasing it. On this flight I noticed low manifold pressure on the left engine during climb out of 6000 ft and by 9000 ft I only had 25 inches, whereas it should have been able to produce 42 inches. While in cruise at 9000 ft I noticed the same engine, the left one's, egt gauge to be lower than normal. Intending to correct the low egt indication, I reduced the mixture on that side. The engine compartment high heat warning sounded and I reduced power and enriched the mixture. The high heat warning extinguished and I increased power. Again the high heat warning light and sound activated and I shut down the left engine feathering the propeller. Having no need to discontinue the flight I continued to ipt, my destination, and landed uneventfully. The problem was later determined to be a hole in the exhaust stack. The purpose for sending in this report is to avoid adverse consequences should anyone from the FAA seek to violate me for bypassing 2 airports which were closer than ipt and could have been used for landing. As the aircraft was performing well at 9000 ft and I did not need to have ATC rerte any aircraft for me, it was indicated that there was no need to change my destination airport, nor report the situation as an emergency.

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Original NASA ASRS Text

Title: PA60 LEVEL 9000 FT UNABLE TO GET FULL PWR ON L ENG, 25 INCHES MANIFOLD PRESSURE VERSUS NORMAL 42 INCHES. EGT LOW ON L ENG. REDUCED MIXTURE, GOT HIGH HEAT WARNING L ENG. REDUCED PWR AND WENT OUT. INCREASED PWR AND HEAT INDICATION RETURNED. SHUT DOWN ENG, NO EMER, CONTINUED TO DEST IPT. FOUND HOLE IN THE EXHAUST MANIFOLD.

Narrative: ON 2 PREVIOUS FLTS I HAD HAD INDICATIONS OF DIRT IN A FUEL INJECTOR. ON THE FIRST FLT THE SIT CORRECTED ITSELF PRIOR TO THE NEXT TKOF. ON THE SECOND FLT THE SIT WAS CORRECTED INFLT BY REDUCING THE MIXTURE RICHNESS, THEN RAPIDLY INCREASING IT. ON THIS FLT I NOTICED LOW MANIFOLD PRESSURE ON THE L ENG DURING CLB OUT OF 6000 FT AND BY 9000 FT I ONLY HAD 25 INCHES, WHEREAS IT SHOULD HAVE BEEN ABLE TO PRODUCE 42 INCHES. WHILE IN CRUISE AT 9000 FT I NOTICED THE SAME ENG, THE L ONE'S, EGT GAUGE TO BE LOWER THAN NORMAL. INTENDING TO CORRECT THE LOW EGT INDICATION, I REDUCED THE MIXTURE ON THAT SIDE. THE ENG COMPARTMENT HIGH HEAT WARNING SOUNDED AND I REDUCED PWR AND ENRICHED THE MIXTURE. THE HIGH HEAT WARNING EXTINGUISHED AND I INCREASED PWR. AGAIN THE HIGH HEAT WARNING LIGHT AND SOUND ACTIVATED AND I SHUT DOWN THE L ENG FEATHERING THE PROP. HAVING NO NEED TO DISCONTINUE THE FLT I CONTINUED TO IPT, MY DEST, AND LANDED UNEVENTFULLY. THE PROB WAS LATER DETERMINED TO BE A HOLE IN THE EXHAUST STACK. THE PURPOSE FOR SENDING IN THIS RPT IS TO AVOID ADVERSE CONSEQUENCES SHOULD ANYONE FROM THE FAA SEEK TO VIOLATE ME FOR BYPASSING 2 ARPTS WHICH WERE CLOSER THAN IPT AND COULD HAVE BEEN USED FOR LNDG. AS THE ACFT WAS PERFORMING WELL AT 9000 FT AND I DID NOT NEED TO HAVE ATC RERTE ANY ACFT FOR ME, IT WAS INDICATED THAT THERE WAS NO NEED TO CHANGE MY DEST ARPT, NOR RPT THE SIT AS AN EMER.

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.