WATER LEAKS AT THE COWL AREA - DIAGNOSIS AND REPAIR

THIS BULLETIN COVERS THE DIAGNOSIS AND REPAIR OF COWL WATER LEAKS. THE SPECIFIC AREAS INCLUDED ARE THE HEATER - A/C MODULE, THE COWL SEAMS AND THE COWL GROMMETS AND SCREWS. SYMPTOMS THE FOLLOWING SYMPTOMS MAY INDICATE A COWL WATER LEAK: - WATER IN REAR FLOOR AREA - WATER DRIPPING ON LEGS OR FEET - WATER ON TOP OF OR UNDER CARPET - MUSTY ODOR DUE TO WATER TRAPPED UNDER CARPET LOCATING AND REPAIRING LEAK THE VEHICLE MAY HAVE TO BE WATER TESTED TO PINPOINT THE SPECIFIC AREA OF WATER ENTRY. REFER TO SECTION 1 OF THE FISHER BODY SERVICE MANUAL FOR WATER TESTING PROCEDURES. LISTED BELOW ARE SOME SPECIFIC AREAS THAT SHOULD BE CHECKED FOR LEAKS AND PROCEDURES TO REPAIR THEM. HEATER - A/C MODULE: 1) CHECK THE HEATER - A/C MODULE MOUNTING BOLTS TO INSURE THAT THEY ARE TIGHT. - IF NOT, THE WINDSHIELD LOWER CHROME MOULDING MUST BE REMOVED TO ACCESS THE UPPER MODULE MOUNTING BOLTS. - TIGHTEN THE BOLTS TO 2-4 N.M (18-35 IN. LB.) IN THE SEQUENCE SHOWN IN FIG. 1. 2) CHECK FOR PROPER APPLICATION OF SEALER AROUND THE HEATER - A/C MODULE. - SEALER SHOULD BE APPLIED ONLY TO THE TOP AND SIDES OF THE MODULE FLANGE AS SHOWN IN FIG. 1. COWL SEAMS: 1) CHECK FOR PROPER SHIMMING OF THE FENDERS. - INCORRECT SHIMMING WILL PLACE EXTRA STRESS ON THE COWL SEAM. - LOOSEN BOLT SHOWN IN FIG. 2. - IF EXCESSIVE GAP, ADD SHIMS. - TIGHTEN BOLT. 2) CHECK FOR PROPER NUMBER AND LOCATION OF SPOTWELDS AS SHOWN IN FIG . 3. - CORRECT AS NECESSARY. 3) CHECK THE SEAM BETWEEN THE LOWER HINGE PILLAR PANEL TO THE DASH PANEL FOR SEALER PLACEMENT OR CRACKING. - PROPER SEALING OF THE COWL SEAM INVOLVES A THUMB GRADE SEALER APPLIED UNDER A FLO-ON SEALER IN THE LOCATIONS SHOWN IN FIGURES 4 AND 5. FRONT OF DASH SEALING: 1) CHECK ALL HOLES IN DASH THAT WIRING HARNESSES OR CABLES PASS THROUGH FOR SEALER. - THERE SHOULD BE SEALER OVER EACH OF THE AREAS INDICATED IN FIG. 6. - SEAL AS REQUIRED. FINAL CHECK AND CLEAN-UP: 1) CHECK FOR WATER UNDER THE CARPET. - LIFT THE CORNER OF THE CARPET UP TO CHECK FOR TRAPPED WATER. - CHECK THE CONDITION OF THE FLOOR PAN. - CORRECT AS NECESSARY. 2) CHECK FOR UNPLEASANT MILDEW ODOUR. - IF ODOUR IS PRESENT, REPLACE THE MATTING UNDER THE CARPET. - SCRUB THE FLOOR PAN AND THE BACK OF THE CARPET WITH LYSOL DISINFECTANT OR EQUIVALENT. SUBJECT: WATER LEAKS ON 1982 "J" CARS VEHICLES AFFECTED: 1982 "J" STYLE VEHICLES THE FOLLOWING WILL AID IN WATER LEAK DIAGNOSIS AND CORRECTION. 1) CONDITION: WATER ENTRY THROUGH THE EVAPORATOR CORE PIPE IN FRONT OF THE DASH HOLES (FIGURE 1, VIEW A, ITEM 1). IDENTIFICATION: CARPET WILL BE WET FROM THE UNDERSIDE AND SOAKED THROUGH DIRECTLY IN UNDER THE PIPE ENTRY INTO THE PASSENGER COMPARTMENT. CORRECTION: SEAL FROM THE ENGINE COMPARTMENT SIDE-PIPE TO THE EDGE OF THE METAL WITH A MODERATELY THICK SEALER OVER THE GASKET. 2) CONDITION: WATER ENTRY AROUND THE HEATER FRESH AIR VENT VALVES (FIGURE 1, ITEM 3) RIGHT-HAND OR LEFT-HAND. IDENTIFICATION: WATER WILL LEAK ON THE CARPET, ONTO THE HUSH PANEL(S) , ETC. CORRECTION: REMOVE THE VALVE(S) AND OVERSEAL THE GASKET AND SCREW HOLES WITH 3M08648 OR EQUIVALENT SEALER. 3) CONDITION: WATER ENTRY THROUGH THE CRUISE CONTROL KNOCK-OUT PLUG ON UNITS BUILT WITHOUT CRUISE CONTROL (FIGURE 1, ITEM 4). IDENTIFICATION: WATER WILL LEAK FROM THE HOLE DOWN TO THE CARPET, USUALLY IN UNDER THE CARPET. CORRECTION: SEAL THE HOLE OPENING AROUND THE EDGE WITH 3M08648 OR EQUIVALENT SEALER. 4) CONDITION: WATER ENTRY FROM PLENUM CHAMBER THROUGH THE TWO UPPER LEFT-HAND HEATER OR AIR CONDITIONING BLOWER AND AIR INLET ASSEMBLY MOUNTING HOLES (FIGURE 2). IDENTIFICATION: WET CARPET DIRECTLY BELOW THE HEATER CASE -- MAY BE WET ON TOP OR UNDERSIDE OF CARPET. CORRECTION: CHECK FOR SEALER SKIPS INSIDE THE PLENUM BETWEEN THE FRONT OF THE DASH PANEL AND THE PLENUM FRONT PANEL AND RESEAL AS SHOWN WITH 3M08648 OR EQUIVALENT SEALER (FIGURE 2). 5) CONDITION: WATER ENTRY THROUGH THE HEATER OR AIR CONDITIONING BLOWER AND AIR INLET ASSEMBLY MOUNTING HOLES (FIGURE 1, VIEW A, ITEM 2 - SCREW HOLES; AND, FIGURE 2, ITEM 1). IDENTIFICATION: WET CARPET DIRECTLY BELOW THE HEATER CASE -- MAY BE WET ON TOP OR UNDERSIDE OF CARPET. CORRECTION: SEAL THE UPPER LEFT-HAND HORIZONTAL (TWO) AND LEFT-HAND VERTICAL (ONE) BLOWER AND INLET ASSEMBLY MOUNTING BOSSES FROM THE MOUNTING GASKET AROUND THE BOSSES AND BACK TO THE MOUNTING GASKET. USE 3M08648 OR EQUIVALENT SEALER. 6) CONDITION: WATER ENTRY FROM AROUND THE PLENUM AIR CONDITIONING RECIRCULATION VALVE ASSEMBLY (FIGURE 3, ITEM 1). IDENTIFICATION: WATER WILL LEAK ON THE RIGHT SIDE OF THE DASH ONTO THE HUSH PANEL, IP WIRING, GLOVE BOX, AND/OR CARPET. CORRECTION: REMOVE THE AIR INLET VALVE ASSEMBLY FROM THE PLENUM AND SEAL THE GASKET TO THE PLENUM SURFACE WITH 3M08648 OR EQUIVALENT SEALER AND REINSTALL THE VALVE ASSEMBLY. 7) CONDITION: WATER ENTRY AT THE FRONT BODY HINGE PILLAR (LEFT-HAND OR RIGHT-HAND) TO THE PLENUM AND THE FRONT DASH SEAM (FIGURE 3, ITEM 2, ADDED NOTE; AND, FIGURE 1, ITEM 5, ADDED NOTE). IDENTIFICATION: WATER WILL LEAK DOWN FROM THE SEAM AND WET THE CARPET FROM THE UNDERSIDE AT THE FORWARD OUTBOARD CORNER OF THE CARPET. CORRECTION: REMOVE THE FENDER AND SEAL THE SEAM AS REQUIRED WITH 3M08648 OR EQUIVALENT SEALER. 8) CONDITION: WATER ENTRY AT THE EFI WIRING HARNESS AND RIGHT-HAND SIDE OF THE CAR (FIGURE 4). IDENTIFICATION: WATER LEAKING ONTO THE RIGHT-HAND DASH PANEL OR DOWN THE FIREWALL AND ONTO THE CARPET. CORRECTION: SEAL AROUND THE EFI WIRING GROMMET TO THE FRONT OF THE DASH OPENING. SEAL THE SPLIT IN THE GROMMET ELBOW. SEAL THE WIRES INSIDE THE CONDUIT OR TAPE AROUND THE O.D. OF THE CONDUIT WITH WATERPROOF TAPE PROVIDING THAT THE SPLIT IN THE CONDUIT IS UP. (WATER WILL ENTER THE SPLIT IN THE CONDUIT AND FOLLOW THE WIRES BACK THROUGH THE I.D. OF THE GROMMET AND INTO THE PASSENGER COMPARTMENT.) THE CONDUIT AND ELBOW SHOULD BE ROUTED IN A DOWNWARD DIRECTION FROM THE GROMMET FORWARD. 1.CONT. IN PASSENGER COMPARTMENT 2.ELBOW SHOULD POINT DOWN 3.CYCLING PRESS. SWITCH 4.A/C HARN. CONN. 5.M.A.P. SENSOR 6.THERMISTOR 7.W/S WIPER MOTOR 8.A/C CONSTANT RUN DELAY 9.A/C CONTROL RELAY 10.FUEL PUMP RELAY 9) CONDITION: WATER ENTRY AT THE REAR EDGE OF THE FRONT DOOR(S) ON 69 STYLES. IDENTIFICATION: WATER WILL SEEP DOWN THE FORWARD EDGE OF THE DOOR CENTRE POST ONTO THE CARPET. THE WATER MAY SEEP IN UNDER THE CARPET OR ON TOP OF IT. CORRECTION: REMOVE THE DOOR CENTRE POST TRIM AND REMOVE FROM THE DOOR CENTRE POST FLANGE THE DOOR WEATHERSTRIP SEAL 6" BELOW TO 6" ABOVE THE DOOR LOCK STRICKER. REWORK THE FLANGE BY BENDING THE FLANGE OUTBOARD 5MM AT THE LOCK STRIKER BOLT AND TAPERING OFF TO ZERO BEND 6" ABOVE AND BELOW THE STRIKER BOLT. REINSTALL THE WEATHERSTRIP AND POST TRIM. THIS REPAIR PLACES MORE PRESSURE ON THE DOOR WEATHERSTRIP BY THE DOOR AT THE POINT OF WATER ENTRY. 10) CONDITION: REAR COMPARTMENT LEAKS ON 77 STYLES AT THE DRIP RAIL JOINTS OR HATCH HINGE HOLES IN THE ROOF. IDENTIFICATION: WATER WILL LEAK INTO THE REAR COMPARTMENT FROM THE HATCH OPENING TRIM JOINTS OR FROM IN UNDER THE TRIM ONTO THE FLOOR. CORRECTION: REMOVE THE LEFT-HAND OR RIGHT-HAND DRIP RAIL AND SEAL THE ROOF TO 1/4 JOINT AND/OR REMOVE THE HATCH HINGE BOLTS FROM THE ROOF JOINT AND SEAL THE HOLE USING 3M08648 OR EQUIVALENT SEALER.

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