ENGINE OIL PAN GASKET CHANGE SEAL INSTALLATION PROCEDURE

THE USE OF RTV IN PLACE OF THE REAR OIL PAN SEAL IN 250 L6 ENGINES BEGAN DURING THE 1979 MODEL YEAR. AT THAT TIME THE REAR MAIN BEARING CAP OIL SEAL GROOVE WAS ELIMINATED AND ONLY A SHALLOW CUT WAS MADE TO CONTROL THE THICKNESS OF THE RTV. AT SOP 1980 THE FRONT OIL PAN SEAL AND THE OIL PAN SIDE RAIL GASKET WERE ALSO REPLACED WITH RTV. AT THIS TIME THE NUMBER OF OIL PAN ATTACHING BOLTS WAS REDUCED FROM 12 PER SIDE OR 24 TOTAL TO 8 PER SIDE OR 16 TOTAL. THIS WAS ACCOMPLISHED BY ELIMINATING 4 BOLT LOCATIONS ON EACH SIDE. THEREFORE, THE LOCATION OF THE REMAINING HOLES DO MATCH WITH THE ORIGINAL OIL PAN ATTACHING HOLES. THE 1980 STYLE OIL PAN AND/OR ENGINE BLOCK ARE USED TO SERVICE PAST MODEL VEHICLES. ANY AND ALL COMBINATIONS ARE ACCEPTABLE BY USING THE FOLLOWING GUIDELINES: 1.RTV CAN BE USED IN PLACE OF THE FRONT OIL PAN SEAL AND SIDE RAIL GASKET ON EITHER STYLE OIL PAN, HOWEVER, RTV MUST BE USED ON THE NEW STYLE OIL PAN (16 BOLT HOLE ATTACHMENT). 2.A REAR OIL PAN SEAL MUST BE USED WHEN THE DEEP GROOVE IS MACHINED IN THE REAR MAIN BEARING CAP. 3.RTV MUST BE USED WHEN A SHALLOW GROOVE OR NO GROOVE IS MACHINED IN THE REAR MAIN BEARING CAP. THE FOLLOWING ILLUSTRATION DEPICTS THESE SAME THREE GUIDELINES. ** ILLUSTRATION **

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