How to Replace a Front Windshield

Windshields only need to be replaced when there is damage that is sufficient enough to impair your vision when driving. Modern windshields are held in place by a powerful, yet flexible, urethane molding. Once the molding cures, it will flex, but not allow the windshield to crack under normal driving conditions. The Windshield itself is made of tempered glass. Even if you did get into an auto collision, the glass is designed to break into small pieces to avoid cutting you. However, even a good design is no match for a well-placed stone or a full-on collision. Stone chips are very common and can lead to a compromise in the integrity of the windshield. If you develop a crack that is more than an inch in length, you should seriously consider replacing the front windshield.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• Replacement windshield
• Flat-tip screwdriver
• Automotive cutting knife
• Cleaning brush
• Bucket of water
• Clean rags
• Razor blade
• Urethane primer
• Urethane
• Electric caulking gun
• Nitrile gloves

1. Pry the plastic trim molding away from the windshield using a flat-tip screwdriver. Depending on the vehicle, this may or may not require a lot of time. Some vehicles use extensive trim around the windshield, others have no trim and instead use rubber molding. This molding will have to be cut out or carefully pulled out using the screwdriver.

2. Cut the urethane molding and break the seal holding the windshield to the vehicle. This molding is extremely tough, so it may take an hour or more to completely cut through all of this material.

3. Pull the windshield off and set it aside.

4. Scrape of residual molding on the vehicle down to 3 mm using a razor blade.

5. Clean off the vehicle's pinchweld where the new windshield will be installed. Use a brush and water to brush away any loose molding and debris. Then dry the area with a clean rag.

6. Apply the urethane primer to the frit band on the new windshield. The frit band is the black strip running around the perimeter of the new windshield. This band needs to be activated by the primer in order to adhere to the urethane.

7. Apply the urethane to the pinchweld area where the windshield will be placed. Use an electric caulk gun for better consistency in the application process. Use the 3 mm band of old urethane that is still in the pinchweld area of the frame as a guide to place the new urethane. It's OK to apply the new urethane over the old as long as it has been trimmed properly to 3 mm.

8. Align the windshield so that there is proper orientation on the frame. Align the top, bottom and sides of the windshield by sight as long as the frit band makes contact with the urethane.

Tips & Warnings

• When installing the windshield, after applying the urethane, wear nitrile gloves to prevent the oils from your hands from interfering with the activating agent in the urethane primer.
• Do not touch the frit band when installing the windshield as it may interfere with the activation process of the band.

References

• "Body Repair & Painting Manual"; Chilton Motorbooks; 1991