What was found
ON FLT NR 535, ATL-ATL, AIR RETURN, DURING THE CLIMB THE CAPTAIN NOTICED NR 2 ENGINE OIL PRESSURE AT 100 PSI. THE AIRCRAFT LANDED UNDER THE MAXIMUM LANDING WEIGHT. MAINTENANCE FOUND A BAD CANNON PLUG. REMOVED AND REPLACED THE CANNON PLUG, OPS CHECKED GOOD IAW MM 79-31. (M)