REMOVE OIL SAFETY VALVE SUB-ASSEMBLYREMOVE OIL FILTER UNION Engine Oil Cooler -- Disassembly 1. REMOVE OIL SAFETY VALVE SUB-ASSEMBLYRemove the plug, gasket, spring and safety valve. 2. REMOVE OIL FILTER UNIONUsing a 12 mm socket hexagon wrench, remove the union.