WINDSHIELD WATER LEAK CAUSE AND REPAIR PROCEDURE

WINDSHIELD WATER LEAK CORRECTION PROCEDURES IN SECTION 2D-PAGE 42 OF THE 1981 LIGHT DUTY TRUCK SERVICE MANUAL REQUIRE FURTHER EXPLANATION. IT IS NOT NECESSARY TO REMOVE THE PLASTIC REVEAL MOULDINGS TO CORRECT WATER LEAKS IN MOST CASES. 1.TO LOCATE THE SOURCE OF A WATER LEAK, REMOVE THE WINDSHIELD GARNISH MOULDING IF SO EQUIPPED, FROM THE INSIDE OF THE VEHICLE. 2.REMOVE THE WINDSHIELD SUPPORT MOULDING, FIGURE NO. 1, FROM THE INSIDE OF THE VEHICLE WITHOUT REMOVING THE WINDSHIELD. 3.LOCATE THE POSITION OF THE WATER LEAK BY APPLYING LOW AIR PRESSURE TO THE URETHANE SEAL AROUND INSIDE OF THE WINDSHIELD WHILE WATER OR A SOAPY SOLUTION IS SPRAYED TO THE EXTERIOR WINDSHIELD REVEAL MOULDING AREA. IF BUBBLES APPEAR AT THE WINDSHIELD AREA, A WATER LEAK EXISTS IN THE URETHANE SEAL. IF THE LEAK IS DUE TO A DISRUPTION IN THE URETHANE BOND TO THE GLASS, THE LEAK CAN BE REPAIRED WITH THE ADDITION OF URETHANE ADHESIVE (GM KIT NO. 993110) OR COMPARABLE RESEALANT (SUCH AS IS AVAILABLE FROM KENT OR DOMINION SURE SEAL) IF A MINOR LEAK IS OBSERVED. TO APPLY SEALER IN THE WINDSHIELD REVEAL MOULDING AND URETHANE AREA, USE A HEAT GUN TO WARM THE AREA SLIGHTLY AND THEN CAREFULLY MOVE THE PLASTIC REVEAL MOULDING WITH A FLAT BLADED TOOL SUFFICIENTLY TO ALLOW THE SEALER TO BE INSERTED IN THE LEAK AREA. 4.WATER MAY BE LEAKING THROUGH A PINCH WELD SEAM IN THE TOP OF THE WINDSHIELD OPENING BECAUSE OF SEALER VOIDS IN THE FRONT ROOF DRIP RAIL AND NOT THE URETHANE BOND, FIGURE NO. 2. TO DETERMINE IF A WATER LEAK EXISTS IN THE ROOF DRIP RAIL SEALER, REMOVE ONE SUN VISOR ASSEMBLY. APPLY LOW PRESSURE AIR THROUGH THE SUN VISOR ASSEMBLY OPENING AND AT THE SAME TIME, APPLY WATER OR A SOAPY SOLUTION TO THE EXTERIOR ROOF DRIP RAIL AREA. IF A LEAK EXISTS IN THIS AREA, BUBBLES SHOULD APPEAR IN THE WATER BEING APPLIED TO THE OUTSIDE ROOF DRIP RAIL AREA. IN THESE INSTANCES THE ROOF DRIP RAIL SHOULD INITIALLY BE PREPPED WITH A CLEANER, (SUCH AS IS AVAILABLE FROM KENT #32180 OR DOMINION SURE SEAL #B.S.S.). THEN JOINT AND SEAM SEALER, WHICH CAN LATER BE PAINTED (SUCH AS IS AVAILABLE FROM KENT #32130 OR DOMINION SURE SEAL #C.S.C.), SHOULD BE APPLIED.

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.