What was found
PILOT REPORTED AT 2,400 RPM, NO CLIMB POWER. TRIED ADJUSTING MIXTURE SETTINGS, NOTHING WORKED. ENGINE COUGHED ON DOWNWIND, ACFT WOULD NOT CLIMB. MAINT ATTEMPTED ENGINE START AFTER PARKING ACFT. ENGINE WAS VAPOR LOCKED, WITH ELEC BOOST PUMP ON AND MIXTURE IN FULL RICH, NO FUEL FLOW COULD BE ATTAINED, NO FUEL WOULD FLOW FROM DRAIN. AFTER ENG COOLED, APPROX 1 HOUR, ENGINE WAS STARTED, OIL TEMP INDICATED 150 DEGREES FAHRENHEIT. ENGINE OPERATION WAS NORMAL, FULL POWER COULD BE DEVELOPED, AND MAGNETO CHECK NORMAL. ADJ MADE TO THE IDLE MIXTURE TO ENRICH IT, AND THE IDLE SPEED RE-ADJUSTED. AIRCRAFT TEST FLOWN, RELEASED FOR FLIGHT WITH NO ABNORMALTIES NOTED. ENGINE FUEL SERVO REPLACED IN JULY, SAME PROBLEM.(X)