Narrative:

This report describes 2 related incidents during flight testing following the installation of an overhauled engine. 2 separate flights were conducted in the immediate vicinity of the airport. The initial test flight was terminated after 15 minutes due to a loss of engine power at an altitude of 6;000 ft. A precautionary landing was conducted without incident but the engine quit on exiting the runway. At this time; fuel was observed draining from the cowling. The fuel was shut off and the aircraft was towed to a maintenance hangar. Inspection by mechanics indicated a stuck carburetor float; most probably due to foreign matter. Following repair; reassembly; and an extensive run-up; a second flight was conducted in order to continue engine test and break-in; including a climb to 8;500 ft. I then descended to 6;500 ft and orbited above the airport. During this time; higher than normal cruise power settings were used in accordance with the engine shop's recommended break-in procedure. After approximately 1 hour of flight; I began a descent in order to enter the traffic pattern. Shortly afterwards; the engine began to run rough and I expedited descent and a return to the field while attempting to determine the cause. Upon entering a high downwind leg; fuel pressure dropped to zero and the engine quit completely. Restart was unsuccessful. The aircraft was landed on the in-use runway without incident and coasted to a stop on a taxiway. Inspection by mechanics indicated that although the gauges indicated fuel was remaining in both tanks (1/8 on both sides); the tanks were below usable levels and the engine had died of fuel starvation. For both flights that day; the amount of fuel on board had been estimated based on flight times; not by direct measurement. By that estimate; 1 hour 40 minutes of fuel was on board for the planned 1 hour second test flight. Extended ground operations combined with fuel lost during the episode with the stuck float resulted in less fuel available than expected; leading to running out of fuel after approximately 1 hour 10 minutes of flight.

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Original NASA ASRS Text

Title: C172 pilot reports two consecutive precautionary landings while performing test and break-in of rebuilt engine. Carburetor malfunction causes the first and fuel starvation causes the second when fuel that is lost and wasted during the carburetor malfunction is not considered.

Narrative: This report describes 2 related incidents during flight testing following the installation of an overhauled engine. 2 separate flights were conducted in the immediate vicinity of the airport. The initial test flight was terminated after 15 minutes due to a loss of engine power at an altitude of 6;000 FT. A precautionary landing was conducted without incident but the engine quit on exiting the runway. At this time; fuel was observed draining from the cowling. The fuel was shut off and the aircraft was towed to a maintenance hangar. Inspection by mechanics indicated a stuck carburetor float; most probably due to foreign matter. Following repair; reassembly; and an extensive run-up; a second flight was conducted in order to continue engine test and break-in; including a climb to 8;500 FT. I then descended to 6;500 FT and orbited above the airport. During this time; higher than normal cruise power settings were used in accordance with the engine shop's recommended break-in procedure. After approximately 1 hour of flight; I began a descent in order to enter the traffic pattern. Shortly afterwards; the engine began to run rough and I expedited descent and a return to the field while attempting to determine the cause. Upon entering a high downwind leg; fuel pressure dropped to zero and the engine quit completely. Restart was unsuccessful. The aircraft was landed on the in-use runway without incident and coasted to a stop on a taxiway. Inspection by mechanics indicated that although the gauges indicated fuel was remaining in both tanks (1/8 on both sides); the tanks were below usable levels and the engine had died of fuel starvation. For both flights that day; the amount of fuel on board had been estimated based on flight times; not by direct measurement. By that estimate; 1 hour 40 minutes of fuel was on board for the planned 1 hour second test flight. Extended ground operations combined with fuel lost during the episode with the stuck float resulted in less fuel available than expected; leading to running out of fuel after approximately 1 hour 10 minutes of flight.

Data retrieved from NASA's ASRS site as of April 2012 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.