When replacing a windshield yourself, the quality of the weatherproof seal you obtain is very important. You don't want the elements seeping into the interior of your car because of a bad seal. With care and patience, you can create a good seal for the windshield gasket on your car.
Remove the old windshield gasket from the windshield opening. Take care to remove every trace, particularly if some of the gasket has corroded into the frame.
Place the new windshield on a towel-covered kitchen counter or a set of carpet-covered sawhorses. The surface you place the windshield on must be padded to protect the glass, but you also want to protect the surface from the mess that will be caused by the windshield sealer application.
Use a crayon to mark the bottom center of the windshield on the glass. Use a tape measure to measure from end to end to determine the true center.
Attach the windshield gasket to the windshield, aligning the joint with the crayon mark at the bottom. Work the gasket around the perimeter of the windshield.
Apply windshield gasket sealer (butyl cement) beneath the forward edge of the gasket. Do this by lifting back the edge of the gasket and brushing the sealer between it and the glass, making sure not to miss any spots. This is a messy job, but an essential one to produce a quality seal.
Use a soapy solution to lubricate the outer edge of the gasket or the windshield opening.
Insert the window cord into the groove of the windshield gasket and tape the ends to the inside of the glass.
Place the windshield into the window opening. The best way is to put the bottom in first and then lower the top in and push down.
Pull the cord out of the groove on the gasket to seal it into the windshield frame.
Use mineral spirits to clean excess windshield sealer from the windshield when you are finished.
