A CESSNA 210N ACFT WITH TSIO-510 ENGINE EXPERIENCED LOW OIL PRESSURE AND ENGINE FAILURE ON INITIAL FLIGHT AFTER A TWO CYLINDER OVERHAUL.

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THE ACFT CAME IN TO HAVE 2 CYLINDERS OVERHAULED BECAUSE OF LOW COMPRESSION. I DID NOT COME INTO THE PROJECT UNTIL THE CYLINDERS CAME BACK FROM THE OVERHAUL SHOP. THE OVERHAUL SHOP PROVIDED THE PISTON RINGS AND THE CYLINDER GASKET KITS. AT THAT TIME I VERIFIED THAT THE RINGS WERE THE RIGHT ONES FOR THIS INSTALLATION. THE GASKET KIT APPEARED TO BE THE RIGHT ONE; SO I DIDN'T VERIFY THE PART NUMBERS OF ALL THE GASKETS. I PROCEEDED TO INSTALL THE CYLINDERS IN ACCORDANCE WITH THE MAINT MANUAL. I TORQUED THE CYLINDER FLANGE NUTS IN ACCORDANCE WITH THE MANUFACTURER SPECS AND HAD A CO-WORKER RECHK THE TORQUES. AT THAT POINT; THE CO-WORKER PROCEEDED TO FINISH THE INSTALLATION OF THE INTAKE AND EXHAUST. THE TEST RUN SHOWED NORMAL ENG FUNCTION AND HE RETURNED THE ACFT TO SVC. ON THE INITIAL FLT BY THE OWNER; HE WAS CLBING THROUGH 14000 FT WHEN HE NOTICED LOW OIL PRESSURE. SHORTLY AFTER THAT HE LOST MANIFOLD PRESSURE. AT THAT POINT HE RETURNED TO THE FIELD IMMEDIATELY AND HAD US LOOK AT THE PROB. AFTER TROUBLESHOOTING; WE DECIDED TO REMOVE THE CYLINDERS FOR INSPECTION. THE FIRST THING THAT WE FOUND WAS THE CYLINDER FLANGE NUTS WERE VERY LOOSE AND IN SOME CASES ONLY FINGER TIGHT. WE THEN HAD DIFFICULTY REMOVING THE CYLINDERS. WHEN WE FINALLY GOT THEM OFF WE FOUND THE CYLINDER BASE O-RINGS TO HAVE MELTED INTO THE SPACE IN BTWN THE CYLINDER AND THE CRANK CASE. WE ALSO FOUND THE OIL SCRAPER RING TO BE SEIZED ON ONE PISTON AND WE FOUND HALF OF THE SKIRT BROKEN OFF THE OTHER PISTON AND MOST OF THE OIL SCRAPER RING MISSING. AT THAT POINT WE DECIDED TO SEND THE CYLINDERS OUT TO A DIFFERENT OVERHAUL SHOP FOR AN INDEPENDENT OPINION ON WHAT HAPPENED. THEY TOLD US THAT ALTHOUGH THE OIL SCRAPER RING WAS INSTALLED PER INDUSTRY STANDARD; THAT THEY NORMALLY INSTALLED THIS PARTICULAR BRAND OF OIL SCRAPER RING WITH THE PART NUMBER FACING DOWN; CONTRARY TO INDUSTRY STANDARD. THEY STATED THAT THE OIL SCRAPER RING DOESN'T PROVIDE ADEQUATE LUBRICATION WHEN THE RING IS INSTALLED WITH THE PART NUMBER FACING UP. WHEN WE CONTACTED THE SHOP THAT OVERHAULED THE CYLINDERS TO ASK WHAT THEIR METHOD OF INSTALLING THE OIL SCRAPER RINGS WAS; THEY SAID IT WAS TO INSTALL THEM WITH THE PART NUMBER UP. THEY ALSO TOLD US THAT WE WERE SENT A CYLINDER GASKET KIT FOR AN IO-470 INSTEAD OF A GASKET KIT FOR AN IO-520; STATING THEY WERE IDENTICAL. WE DECIDED TO CONTACT THE MANUFACTURER OF THE GASKET KIT AND ASK THEM IF THERE WAS ANY DIFFERENCE IN THE TWO KITS. THE MANUFACTURER TOLD US THAT THE ONLY DIFFERENCE WAS THE CYLINDER BASE O-RING WAS THICKER. I BELIEVE THAT WHAT HAPPENED; BASED ON THE FACTS GIVEN; IS THAT THE ACFT LOST MANIFOLD PRESSURE ON THE INITIAL FLT DUE TO LOW OIL PRESSURE BECAUSE THE OIL PASSAGEWAYS WERE BECOMING CLOGGED WITH METAL; THEREFORE; NOT ALLOWING THE WASTE GATES FOR THE TURBOCHARGER TO CLOSE. I THINK THE PISTON SKIRT BROKE OFF FROM THE LACK OF TORQUE ON CYLINDER FLANGE NUTS. THE LOW TORQUE WAS A RESULT OF THE O-RINGS BEING TOO THICK AND QUICKLY GAVE WAY UNDER THE HEAT AND PRESSURE OF THE ENG RUNNING. OTHER CONTRIBUTING FACTORS MAY HAVE BEEN THE OIL SCRAPER RINGS NOT PROVIDING ADEQUATE LUBRICATION DUE TO THE WAY THEY WERE INSTALLED. THINGS I WILL DO DIFFERENTLY IN THE FUTURE: I WILL VERIFY ALL PARTS WERE THE CORRECT ONES FOR THE INSTALLATION AND I WILL USE ORIGINAL MANUFACTURER RINGS.