How To Replace Your Own Car Windshield

If your windshield is cracked by a flying rock or a stray baseball, no need to panic-it can be easily repaired. You can even do it yourself, following these instructions.

Begin by obtaining a replacement windshield for your vehicle. These can be bought new or reclaimed from a wrecker's yard, in which case check the windshield for chips and cracks with your own eyes before handing over any money.

If you are moving the detached windshield in your vehicle, use lots of cushioning such as blankets and duvets to prevent damage in transit. If second hand, the windshield will not be ready to fit.

The existing urethane bead will need to be either removed or trimmed down to about 1mm in depth. This is quite easy using a razor blade and a sawing motion.

Next, remove the plastic surround side and top moldings correctly. Don't pry the clips that hold them on; these clips are small plastic pieces specific for the vehicle and its molding.

Cut the urethane from the outside between the glass and the pinchweld, using a cold knife. Depending on tools used and experience, this can take anywhere from fifteen minutes to an hour.

The urethane which holds the windshield in place is flexible but extremely strong; this allows the glass to move and not crack from every stress placed on it during driving. This stuff is tough, up to 1000 psi.

Practice is the key, how much pressure to put on the razor without breaking it. Practice how long to make your strokes so you don't slip and cut the dash board or the head liner.

It all takes practice but when you are not relying on repeat customers, you can do it fast. The pinchweld has the old urethane about a quarter-inch thick more or less and it needs to be trimmed down to 3/16" or about 3 mm.

Prepare the pinchweld. Clean away any visible dirt with a brush and then plain water.

The old urethane needs to be trimmed down to about 3mm thick. Use a razor blade.

Any rusty areas or areas with loose/damaged urethane will need to be taken back to the metal. Rust problems must be fixed.

Next, prepare the glass with a primer specially matched to the urethane adhesive. The purpose of the primer is to open the molecules of the frit band (the black band around the perimeter of the windshield).

This is done to prepare the glass to accept the molecules of the urethane. If your installer is in a hurry, ignorant or just does not care if your windshield pops out he will skip this step.

After the glass is activated, the molding is attached to the glass and the urethane is next. Apply the urethane with an electric caulking gun.

The best thing for the new urethane to adhere to is the old urethane. It must be clean and free from dirt, oil or other contaminants.

A problem installers have is wind blowing dust onto the pinchweld before the urethane adhesive has been applied. This wind is caused from not only the weather conditions but other vehicles including the big trucks.

The job can be done without an electric gun but it is much more difficult to get a consistent bead, making leaks likely. Place the windshield in, carefully aligning the top bottom and sides by sight alone.

Some vehicles have mounting block for the bottom of the windshield to rest on some do not. Careful not to touch the frit band because the oils and dirt from your hands can contaminate the activated glass and reduce the effectiveness of the activator.

Use gloves, either latex or Nitrile to eliminate contaminates. As you can see, though it is a very involved, delicate process, if the guys down at the repair place can do it, so can you.

There is no reason to spend a fortune on having someone else do what you can easily do yourself. All you need is the proper materials, an hour or two, and patience.

If you try to rush the process or get sloppy, the replacement will not be a success. You must be careful to follow the instructions exactly to ensure that it is done properly and effectively, and won't cause you any problems down the line.