CYLINDER HEAD R/R PROCEDURE CHANGE

1981 OMEGA SERVICE MANUAL UPDATE 2.5L 151 CU. IN. L-4 ENGINE VIN CODE '5' CYLINDER HEAD AND/OR GASKET R&R PROCEDURE THE FOLLOWING IS A REVISED PROCEDURE FOR R&R OF THE CYLINDER HEAD AND/OR GASKET ON THE 1981 OMEGA EQUIPPED WITH A 2.5L L-4 ENGINE. REMOVAL: 1.HOIST CAR. 2.DRAIN COOLING SYSTEM. 3.DISCONNECT EXHAUST PIPE FROM EXHAUST MANIFOLD. 4.LOWER CAR. 5.REMOVE OIL DIPSTICK TUBE. 6.REMOVE AIR CLEANER. 7.REMOVE CARBURETOR ELECTRICAL CONNECTIONS AND VACUUM HOSES. 8.REMOVE EGR BASE PLATE. 9.DISCONNECT HEATER HOSE FROM INTAKE MANIFOLD. 10.REMOVE A.I.R. DISCHARGE PIPE ATTACHMENT BOLT AT INTAKE MANIFOLD. 11.REMOVE LOWER COIL MOUNTING BOLT. 12.REMOVE ELECTRICAL CONNECTIONS FROM IGNITION COIL. 13.DISCONNECT ALL ELECTRICAL CONNECTIONS FROM INTAKE MANIFOLD AND CYLINDER HEAD. 14.REMOVE UPPER ENGINE SUPPORT BOLT FROM ENGINE STRUT. 15.REMOVE A/C COMPRESSOR AND SWING ASIDE. 16.REMOVE GENERATOR BELT. 17.REMOVE A.I.R. PUMP BRACKET BOLT FROM BLOCK. 18.REMOVE TV CABLE FROM INTAKE MANIFOLD. 19.REMOVE THROTTLE CABLE FROM INTAKE MANIFOLD. 20.REMOVE UPPER RADIATOR HOSE FROM CYLINDER HEAD. 21.REMOVE A.I.R. HOSE FROM PIPE ASSEMBLY. 22.REMOVE ROCKER ARM COVER. 23.REMOVE ROCKER ARMS AND PUSH RODS. 24.REMOVE CYLINDER HEAD BOLTS. 25.REMOVE CYLINDER HEAD (WITH ONE MAN'S ASSISTANCE). INSTALLATION: THE GASKET SURFACES ON BOTH THE HEAD AND THE BLOCK MUST BE CLEAN OF ANY FOREIGN MATTER AND FREE OF NICKS OR HEAVY SCRATCHES. CYLINDER BOLT THREADS IN THE BLOCK AND THREADS ON THE CYLINDER HEAD BOLTS MUST BE CLEAN. (DIRT WILL AFFECT BOLT TORQUE). 1.INSTALL A NEW CYLINDER HEAD GASKET IN POSITION OVER DOWEL PINS ON CYLINDER BLOCK. 2.WITH ONE MAN'S ASSISTANCE, CAREFULLY GUIDE CYLINDER HEAD INTO PLACE OVER DOWEL PINS AND GASKETS. 3.COAT HEADS AND THREADS OF CYLINDER HEAD BOLTS WITH SEALING COMPOUND AND INSTALL FINGERTIGHT. 4.TIGHTEN THE CYLINDER HEAD GRADUALLY WITH A TORQUE WRENCH. TIGHTEN BOLTS FOLLOWING SEQUENCE IN FIG. 6A1-24. THE FINAL TORQUE IS 120 N.M (90 FT.LB.). 5.REVERSE REMOVAL PROCEDURE REMAINDER OF INSTALLATION. THIS NEW PROCEDURE ALSO INCREASES THE TIME REQUIRED TO PERFORM THESE OPERATIONS. PLEASE NOTE THE TIME IN THE LABOR TIME GUIDE WILL BE CHANGED TO READ AS FOLLOWS: LABOR OPERATION J0508 J0518 TIME ALLOWANCE 2.5HR. 3.7HR. ADD FOR A/C .3HR. .3HR. ADD FOR A.I.R. .3HR. .3HR. ADD FOR CRUISE CONTROL .2HR. THESE CHANGES WILL BE EFFECTIVE IMMEDIATELY AND WILL BE REPRINTED IN THE NEXT LABOR TIME GUIDE REVISION.

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