As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMBOUT A SLIGHT ODOR OF SMOKE WAS NOTICED IN THE CABIN. STARTED TO RETURN TO BASE WHEN RT OIL PRESSURE LOW LIGHT ILLUMINATED. THIS WAS CONFIRMED BY THE OIL PRESSURE INDICATOR. RT ENGINE WAS SECURED, AN UNEVENTFUL LANDING. FOUND PROPELLER PISTON SEAL O-RING CUT AND ROLLED A LARGE QUANTITY OF OIL WAS FOUND ON COWLING AND INLET TO ENGINE. REPLACED O-RING LEAK AND OPERATIONAL CHECK OK.