As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS PARKED FOR 3 WEEKS. FOUND FUEL/OIL MIX LEAKING FROM MUFFLER EXHAUST PIPE. FUEL LEAKED VIA GRAVITY FROM TANKS THROUGH PUMP, INTO PUMP DRIVE LEVER AREA, THEN, VIA THE ACCESSORY SECTION INTO ENGINE . FOUND ENGINE CRANK CASE FILLED WITH AVGAS. CYLINDERS WERE ALSO FULL OF GAS/OIL MIX AND WERE HYDRAULICALLY LOCKED. FUEL/OIL MIX WAS DRAINING OUT EXHAUST VALVES INTO MUFFLER. NOTE: FUEL DID NOT DRAIN OUT OF DRAIN PORT ON FUEL PUMP. DISASSEMBLED PUMP. DRAIN PORT WAS NOT OBSTRUCTED.