A NAVION B DIVERTED DUE TO HIGH OIL TEMP AND LOW OIL PRESSURE CAUSED BY LOOSE GASKET SEALANT RESTRICTING OIL PORT.

Narrative

SOME TIME LAST YR; A B MODEL NAVION WITH A GO435 LYCOMING ENG HAD A PROP STRIKE AT YYY AIRPARK. DUE TO THE PROP STRIKE; THE ENG WAS TORN DOWN FOR A REBUILD. AN OLD TIME ENG MAN WITH 40 YRS OF BACKGND PERFORMED THE REBUILD UNDER MY SUPERVISION. ALL WORK WAS DONE TO LYCOMING BOOKS AND MANUALS; USING STANDARD PARTS WITH COMPLETE RETURN TO SVC TAGS. ALL TORQUE WRENCHES WERE IN CURRENT CALIBRATION. ON AUG/SAT/01 WITH ABOUT 12 HRS ON THE ENG ON A FLT FROM XXX TO YYY; THE PLT SAW A RISE IN OIL TEMP; AS WELL AS A DROP IN PRESSURE WITH A VIBRATION AT THE SIMI VALLEY PASS. PAX CALLED IN TO ZZZ ARPT FOR A PRECAUTIONARY LNDG. AT NO TIME DID THE ENG QUIT. THE ACFT WAS PLACED IN A HANGAR. THE ENG WAS REMOVED FOR INSPECTION. ON THE DISASSEMBLY; IT WAS FOUND THAT A SPECK OF SEALANT HAD LODGED IN THE OIL PASSAGE OF THE #1 JOURNAL CAUSING T LACK OF LUBE TO THE BEARING; THUS THE CONNECTING ROD FAILED AT THE BUTT END. THE PROBABLE CAUSE OF THE SEALANT WAS ONCE THE ENG WAS REINSTALLED IN THE ACFT WE HAD TO REMOVE THE T DRIVE AND REPLACE IT. THERE WAS THE POSSIBILITY THAT A BIT OF THE SEALANT COMPRESSED INTO THE ACCESSORY CASE THEN WAS CIRCULATED AROUND THE SYS UNTIL IT WAS TRAPPED BY THE OIL PORT. THERE WAS NO DAMAGE TO THE ACFT; NOR INJURIES TO THE PLT OR PAX. TO BEST PREVENT A RECURRENCE OF THIS TYPE OF INCIDENT; USE THE MINIMUM AMOUNT OF SEALANT POSSIBLE. AS A NOTE; THIS IS THE FIRST TIME I HAVE EVER HAD A PROB WITH AN ENG THAT I HAVE OVERSEEN OR REBUILT MYSELF.