Narrative:

Aircraft owner had fire alarm go on in flight. The pilot landed at gon west/O incident. Upon investigation the left engine exhaust stack tail pipe was broken in half and lying in the cowling. The marmon clamp was loose and the clamp at the top was missing. The fire alarm went off due to exhaust gasses that were projected directly on the censor--also cowl flap wires were burned off. The pilot removed the 2 halves of the exhaust system and brought them to our shop in westerly, ri. I welded the pipe and drove to gon to install it. I installed the exhaust tail pipe and tightened the marmon clamp. At this point I noticed the top attachment clamp was nowhere to be found and the cowl flap wires were burned off into the shielding of the motor. I then made a temperature repair by rapping .041 stainless safety wire 3 times around the tailpipe and through the support bracket, and informed the pilot that it was a temporary repair and the aircraft will be flown only to westerly (10 mi) for repairs to the wiring and a new clamp to be reordered and installed. The aircraft took off with full power. At 500' the pilot felt the plane wanting to pull to the left and left engine RPM had dropped to 2500 RPM. Smoke was coming from the engine compartment. The pilot called tower and landed west/O incident. Removal of the cowl revealed the safety wire had not been adequate support for the forward thrust and broke, causing the pipe to turn, burning up the cowl flap and melting the fire sleeve on one of the oil hoses. I have learned not to make temporary repairs, and to use the mfr's service manual for recommended procedures only.

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Original NASA ASRS Text

Title: GA SMA HAD INDICATIONS OF AN INFLT ENGINE FIRE DURING INITIAL CLIMB. A TEMPORARY REPAIR THAT HAD BEEN MADE TO THE EXHAUST MANIFOLD FAILED ON TKOF.

Narrative: ACFT OWNER HAD FIRE ALARM GO ON IN FLT. THE PLT LANDED AT GON W/O INCIDENT. UPON INVESTIGATION THE LEFT ENG EXHAUST STACK TAIL PIPE WAS BROKEN IN HALF AND LYING IN THE COWLING. THE MARMON CLAMP WAS LOOSE AND THE CLAMP AT THE TOP WAS MISSING. THE FIRE ALARM WENT OFF DUE TO EXHAUST GASSES THAT WERE PROJECTED DIRECTLY ON THE CENSOR--ALSO COWL FLAP WIRES WERE BURNED OFF. THE PLT REMOVED THE 2 HALVES OF THE EXHAUST SYS AND BROUGHT THEM TO OUR SHOP IN WESTERLY, RI. I WELDED THE PIPE AND DROVE TO GON TO INSTALL IT. I INSTALLED THE EXHAUST TAIL PIPE AND TIGHTENED THE MARMON CLAMP. AT THIS POINT I NOTICED THE TOP ATTACHMENT CLAMP WAS NOWHERE TO BE FOUND AND THE COWL FLAP WIRES WERE BURNED OFF INTO THE SHIELDING OF THE MOTOR. I THEN MADE A TEMP REPAIR BY RAPPING .041 STAINLESS SAFETY WIRE 3 TIMES AROUND THE TAILPIPE AND THROUGH THE SUPPORT BRACKET, AND INFORMED THE PLT THAT IT WAS A TEMPORARY REPAIR AND THE ACFT WILL BE FLOWN ONLY TO WESTERLY (10 MI) FOR REPAIRS TO THE WIRING AND A NEW CLAMP TO BE REORDERED AND INSTALLED. THE ACFT TOOK OFF WITH FULL PWR. AT 500' THE PLT FELT THE PLANE WANTING TO PULL TO THE LEFT AND LEFT ENG RPM HAD DROPPED TO 2500 RPM. SMOKE WAS COMING FROM THE ENG COMPARTMENT. THE PLT CALLED TWR AND LANDED W/O INCIDENT. REMOVAL OF THE COWL REVEALED THE SAFETY WIRE HAD NOT BEEN ADEQUATE SUPPORT FOR THE FORWARD THRUST AND BROKE, CAUSING THE PIPE TO TURN, BURNING UP THE COWL FLAP AND MELTING THE FIRE SLEEVE ON ONE OF THE OIL HOSES. I HAVE LEARNED NOT TO MAKE TEMPORARY REPAIRS, AND TO USE THE MFR'S SVC MANUAL FOR RECOMMENDED PROCS ONLY.

Data retrieved from NASA's ASRS site as of August 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.