INFO. ON SERVICE OPERATIONS & PROCS. FOR REPL. ENG. ASSY.

REVISION: 04/22/94

THIS BULLETIN IS BEING REVISED TO DISCONTINUE THE 1993 ENGINE EXCHANGE PROGRAM FOR THE 4.6L NORTHSTAR ENGINE. PLEASE DISCARD BULLETIN 316106. ----------------------------------------------------------------------

SUBJECT: INFORMATION ON ELIMINATION OF THE 1993 4.6L ENGINE EXCHANGE PROGRAM AND SERVICE OPERATIONS AND REPAIR PROCEDURES

MODELS: 1993 CADILLAC ALLANTE, ELDORADO AND SEVILLE WITH 4.6L NORTHSTAR ENGINE (VINS Y, 9 - RPOS LD8, L37)

THIS BULLETIN CANCELS THE 1993 4.6L NORTHSTAR ENGINE EXCHANGE PROGRAM AND DEFINES ENGINE SERVICE OPERATIONS AND PROCEDURES FOR THE 1993 L37 (VIN 9) AND LD8 (VIN Y) VERSIONS OF THE 4.6L NORTHSTAR ENGINE. CONTINUE TO EXCHANGE 1994 4.6L NORTHSTAR ENGINES REQUIRING REPLACEMENT OF ANY INTERNAL COMPONENTS. REFER TO CORPORATE BULLETIN 316107 FOR 1994 4.6L ENGINE EXCHANGE PROGRAM PROCEDURES, WHICH REMAIN IN EFFECT UNTIL FURTHER NOTICE.

THE PURPOSE OF THE 4.6L NORTHSTAR ENGINE EXCHANGE PROGRAMS IS TO PROVIDE EARLY PRODUCT FEEDBACK TO INCREASE CUSTOMER SATISFACTION. THE 1993 EXCHANGE PROGRAM WAS SUCCESSFUL IN RECEIVING ENGINES BACK IN A TIMELY MANNER FOR ENGINEERING ANALYSIS AND EVALUATION.

ALL 1993 4.6L NORTHSTAR INTERNAL COMPONENTS ARE AVAILABLE FROM GMSPO. SERVICE PROCEDURES FOR THE 4.6L NORTHSTAR ENGINE ARE OUTLINED IN SECTION 6A2 OF THE 1993 SERVICE INFORMATION MANUAL. TWO GM GOODWRENCH ENGINE ASSEMBLIES ARE CURRENTLY AVAILABLE THROUGH GMSPO FOR THE PURPOSE OF ENGINE ASSEMBLY REPLACEMENT FOR THE 1993 ALLANTE, ELDORADO AND SEVILLE. THESE ENGINE ASSEMBLIES ARE INCOMPLETE AND WILL REQUIRE THE TRANSFER OF THE FOLLOWING COMPONENTS FROM THE ORIGINAL ASSEMBLY:

INTAKE MANIFOLD AND INSULATORS STARTER MOTOR AND BATTERY CABLES EGR VALVE AND GASKET IGNITION SYSTEM AND SPARK PLUG WIRES POWER STEERING PUMP

PART INFORMATION:

DESCRIPTION PART NUMBER ----------- ----------- ENGINE ASSEMBLY 3636797 - L37 (VIN 9) 295 HP ENGINE ASSEMBLY 3636798 - LD8 (VIN Y) 270 HP

ALTHOUGH GM GOODWRENCH ENGINE ASSEMBLIES ARE SHIPPED WITH A QUANTITY OF OIL, THE OIL LEVEL SHOULD BE CHECKED BEFORE STARTING THE ENGINE.

NOTE: WHENEVER IT IS NECESSARY TO INSTALL A 4.6L ENGINE ASSEMBLY INTO A 1993 V, E OR K VEHICLE, THE FOLLOWING MODIFICATIONS **MUST** BE PERFORMED:

THE ATTACHMENT FOR THE PCM GROUND WIRES ON THE RIGHT SIDE OF THE CRANKCASE HAS BEEN REDUCED FROM A 10 MM THREAD TO A 6 MM THREAD. BOTH HARNESS GROUND WIRES MUST HAVE NEW TERMINALS INSTALLED AND BE RESOLDERED. USING 6 MM DIAMETER RING TERMINAL, P/N 2984172, OR EQUIVALENT. THIS CONNECTION IS SHOWN IN THE 1993 ELDORADO/ SEVILLE SERVICE MANUAL ON PAGE 8A-201-19 IN FIGURE 1, CIRCUIT G102.

FIGURES: 1

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER". THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS THAT MAY OCCUR ON SOME VEHICLES, OR TO PROVIDE INFORMATION THAT COULD ASSIST IN THE PROPER SERVICE OF A VEHICLE. PROPERLY TRAINED TECHNICIANS HAVE THE EQUIPMENT, TOOLS, SAFETY INSTRUCTIONS AND KNOW-HOW TO DO A JOB PROPERLY AND SAFELY. IF A CONDITION IS DESCRIBED, DO NOT ASSUME THAT THE BULLETIN APPLIES TO YOUR VEHICLE, OR THAT YOUR VEHICLE WILL HAVE THAT CONDITION. SEE A GENERAL MOTORS DEALER SERVICING YOUR BRAND OF GENERAL MOTORS VEHICLE FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.

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