CAMPAIGN: CATALYTIC CONVERTER NO START/POOR ENGINE PERFORM.

GENERAL MOTORS HAS DETERMINED THAT SOME 1981 "A" AND "F" SERIES MODELS MAY DEVELOP RESTRICTED CATALYTIC CONVERTERS RESULTING IN POOR ENGINE PERFORMANCE OR A NO START CONDITION. TO PREVENT THE POSSIBILITY OF THIS CONDITION OCCURRING, IT WILL BE NECESSARY TO REPLACE THE CATALYTIC CONVERTER ON THE INVOLVED VEHICLES. VEHICLES INVOLVED CHECK THE C.R.I.S. SYSTEM TO DETERMINE IF A SPECIFIC VEHICLE IS INVOLVED IN THIS CAMPAIGN. SERVICE PROCEDURE PART I - INSPECTION 1. RAISE VEHICLE ON HOIST. 2. REFER TO FIGURE 1 FOR LOCATION OF CATALYTIC CONVERTER PART NUMBER. 3. THE CONVERTER NEED NOT BE REPLACED IF IT IS A NEW TYPE BASKETED CONVERTER, P/N 25056619 OR 25056625. PROCEED TO PART III IF REPLACEMENT OF THE CONVERTER IS NOT REQUIRED. 4. IF THE CONVERTER PART NUMBER IS LISTED IN COLUMN 1 OF THE TABLE BELOW, REPLACE THE CONVERTER WITH THE APPROPRIATE CONVERTER PART NUMBER IDENTIFIED IN COLUMN 2 OF THE TABLE. (ALL VEHICLE MODELS LISTED ARE EQUIPPED WITH RPO LS5 4.3 LITER 265 CU. IN. ENGINES). COLUMN 1 ORIGINAL COLUMN 2 NEW DUAL MODEL YEAR VEHICLE DUAL BED BEAD CONV. BEAD CONV. 1981 "F" SERIES 8999593 25056674 1981 "A" SERIES 8999591 25056673 PART II - CONVERTER REMOVAL, PREPARATION AND INSTALLATION 1. RAISE VEHICLE ON HOIST. 2. DISCONNECT AIR SUPPLY PIPE FROM FRONT OF CONVERTER (FIGURE 2-ITEM 4). 3. DISCONNECT INTERMEDIATE PIPE FROM REAR OF CONVERTER (FIGURE 1-ITEM 3). 4. DISCONNECT HANGER BRACKET FROM CONVERTER. 5. LOOSEN FRONT EXHAUST CLAMP TO REMOVE CONVERTER FROM VEHICLE. DISCARD CLAMP. 6. STAND OLD CONVERTER UPRIGHT ON INLET END AND POUR TWO (2) 8 OUNCE CUPS OF WATER INTO OUTLET END (FIGURE 1-ITEM 3) TO CONTROL CATALYST DUST. 7. USING HAMMER AND CHISEL, REMOVE UPPER BED FILL HOLE PLUG FROM OLD CONVERTER BY DRIVING CHISEL BETWEEN THE CONVERTER SHELL AND RIM OF FILL PLUG (FIGURE 1-ITEMS 6 AND 7 FOR DESCRIPTION OF UPPER AND LOWER BEDS). DEFORM FILL PLUG UNTIL IT CAN BE REMOVED WITH PLIERS. 8. HOLD CONVERTER OVER A CLEAN STORAGE PAN (J-34155-2) AND EMPTY CATALYST BEADS BY SHAKING AND TAPPING CONVERTER BELT FLANGE (FIGURE 1-ITEM 2) WITH RUBBER MALLET. NOTICE: IF UPPER BED IS VOID OR NEAR VOID (A CUP OR LESS) OF CATALYST BEADS, THE CONVERTER IS CONSIDERED DAMAGED (INTERNALLY) OR EXPANDED. CATALYST BEADS FOUND IN INTERNALLY DAMAGED OR EXPANDED CONVERTERS ARE NOT TO BE USED IN NEW CONVERTERS. THESE BEADS CAN BE RETURNED VIA EXCHANGE PROGRAM DESCRIBED IN WDDGM BULLETIN IB NO. 83-138. 9. POUR UPPER BED BEADS INTO SIFTING PAN (J-34155-1). SIFT OUT BROKEN BEADS (SMALLER THAN HALF SIZE) INTO A CLEAN BOX. POUR SIFTED BEADS (HALF SIZE AND LARGER) INTO THE OTHER STORAGE PAN (J-34155-2). SET SIFTED BEADS ASIDE FOR NOW. UNUSABLE BEADS AND DUST CAN BE RETURNED VIA EXCHANGE PROGRAM DESCRIBED IN WDDGM BULLETIN IB NO. 83-138. 10.PROP NEW CONVERTER UP AT A 45 DEGREE ANGLE WITH UPPER BED FILL HOLE AT TOP. SEE FIGURE 1-ITEMS 6 AND 7 FOR A DESCRIPTION OF UPPER AND LOWER BEDS). TAP FUNNEL (J-34155-3) INTO CONVERTER HOLE WITH HAMMER (FIGURE 2). 11.INSTALL PACKET OF NEW UPPER BED HEADS FROM KIT P/N 25056799 INTO UPPER BED OF THE NEW CONVERTER. 12.POUR SIFTED UPPER BED BEADS (REFERENCE STEP 9) UPPER BEADS, IF REQUIRED, INTO CONVERTER. TAP BELT FLANGE OF THE CONVERTER WITH RUBBER MALLET TO ALLOW HEADS TO SETTLE. CONTINUE FILLING AND TAPPING UNTIL CONVERTER IS FULL. SEE FIGURE 3-ITEM 1 FOR DEFINITION OF FULL UPPER BED. IF UPPER BED IS FULL, PROCEED TO STEP 13. IF UPPER BED IS NOT FULL, USE LEFTOVER UPPER BED CATALYST BEADS FROM INVOLVED DUAL BED CONVERTERS TO FILL UPPER BED. IF THERE ARE NOT ENOUGH USED UPPER BED BEADS, OBTAIN UPPER BED CATALYST KIT P/N 25056802 AND CONTINUE TO FILL UPPER BED UNTIL FULL. NOTICE: USED UPPER BED BEADS (FROM NON-DAMAGED CONVERTERS) ARE TO BE MIXED WITH NEW UPPER BED BEADS. DO NOT MIX UPPER AND LOWER BEADS. ALSO, DO NOT MIX BEADS FROM CONVERTERS OFF VEHICLES THAT ARE NOT INVOLVED. STORE UNUSED UPPER BED BEADS IN A CLEAN CONTAINER MARKED "UPPER BED." 13. LAY CONVERTER DOWN ON A FLAT SURFACE WITH UPPER BED ON TOP. 14. INSERT FILL PLUG, P/N 8998202, (TWO ARE PROVIDED IN KIT P/N 25056799 INTO UPPER BED FILL HOLE. IF OUTER RIM OF THE FILL PLUG DOESN'T FIT FLAT AGAINST CONVERTER SHELL, REMOVE ENOUGH BEADS SO IT DOES. 15. WITH FILL PLUG IN FILL HOLE, INSERT TOOL (J-3418-1) INTO FILL PLUG (FIGURE 4-ITEM 2). TIGHTEN TOOL TO 35 LBS. FT. (47 N.M AND MAKE SURE PLUG OUTER RIM IS FLAT AND TIGHT AGAINST CONVERTER SHELL. SET NEW CONVERTER ASIDE. 16. REMOVE LOWER BED PLUG FROM OLD CONVERTER USING PROCEDURE DESCRIBED IN STEP 7. 17. HOLD CONVERTER OVER A CLEAN STORAGE PAN (J-34155-2) AND EMPTY CATALYST BEADS BY SHAKING AND TAPPING CONVERTER BELT FLANGE (FIGURE 1-ITEM 2) WITH RUBBER MALLET. 18. SIFT LOWER BED BEADS USING PROCEDURE DESCRIBED IN STEP 9. 19. PROP NEW CONVERTER UP AT 45 DEGREE ANGLE WITH LOWER BED FILL HOLE AT TOP (SEE FIGURE 1-ITEMS 6 AND 7 FOR DEFINITION OF UPPER AND LOWER BEDS). TAP FUNNEL (J-34155-3) INTO CONVERTER FILL HOLE WITH HAMMER FIGURE 2). 20. POUR SIFTED LOWER BED BEADS (REF/ STEP 18) OR NEW LOWER BED BEADS IF REQUIRED, INTO NEW CONVERTER LOWER BED. TAP BELT FLANGE WITH RUBBER MALLET TO ALLOW BEADS TO SETTLE. CONTINUE FILLING AND TAPPING UNTIL CONVERTER IS FULL (REF. FIGURE 3-ITEM 1). IF LOWER BED IS NOT FULL, USE LEFTOVER LOWER BED CATALYST BEADS SAVED FROM INVOLVED DUAL BED CONVERTERS TO FILL LOWER BED. IF THERE ARE NOT ENOUGH USED LOWER BED BEADS, OBTAIN LOWER BED BEAD SERVICE KIT P/N 25056682 (ZONE APPROVAL IS REQUIRED TO OBTAIN THIS KIT), AND CONTINUE FILLING THE LOWER BED UNTIL FULL. NOTICE: THE LEFTOVER LOWER BED BEADS ARE TO BE SAVED FOR FUTURE USE. STORE THEM IN A CLEAN CONTAINER MARKED "LOWER BED." DO NOT MIX UPPER AND LOWER BEADS. ALSO DO NOT MIX BEADS FROM CONVERTERS OFF OF VEHICLES THAT ARE NOT INVOLVED. 21. LAY CONVERTER DOWN ON FLAT SURFACE WITH LOWER BED ON TOP AND INSTALL FILL PLUG USING PROCEDURE DESCRIBED IN STEPS 14 AND 15. 22. INSTALL NEW CONVERTER ON VEHICLE REVERSING REMOVAL PROCEDURES DESCRIBED IN THIS BULLETIN AND REFERENCING APPROPRIATE SERVICE MANUAL. PARTS INFORMATION THE PARTS REQUIRED TO COMPLETE THIS CAMPAIGN ARE TO BE ORDERED FROM WDDGM. TO ENSURE THIS PART WILL BE OBTAINED AS SOON AS POSSIBLE, IT SHOULD BE ORDERED FROM WDDGM ON A C.I.O. ORDER WITH NO SPECIAL INSTRUCTION CODE, BUT ORDER ON AN ADVISE CODE (2).

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.