How to Fix a Leaky Car Window

If you have discovered that your floorboards, seats or car dash are wet following rain or morning dew, it is likely that you have a leaky window, even if you haven't actually seen rain coming in. You may also detect a musty or mildew-like odor in your car that comes from the car's interior regularly getting wet. As long as the cause of the leak is minor, finding and repairing a car window that is leaking is a task that many people can handle on their own.

Difficulty: Moderate

Instructions

Things You'll Need:

    * Garden hose
    * Utility knife or razor blade
    * Rubbing alcohol
    * Polyurethane sealant or silicone caulk
    * Caulking gun
    * Rag
    * Silicone rubber


      Step 1

      Sit in the rear seat of the car and have someone else spray water on the vehicle with a garden hose to locate the window that is leaking. Watch all of the side windows and the windshield to find out where the water is coming in.

      Step 2

      Remove the trim from around the edge of the window that has the leak. Find the seam of the trim, which is generally at the bottom on side windows and at the top corners on the windshield. Pull the trim out from the window slowly and it will pop free of the window edge.

      Step 3

      Inspect the edge of the window for missing caulking or black, mildewed spots in the caulking. Also, look at the edges of the window for cracks or chips in the glass.

      Step 4

      Add new caulking if there is missing or damaged window caulk. Remove the old caulking by carefully trimming it away with a utility knife or razor blade and clean the area thoroughly with rubbing alcohol to remove leftover debris. Don't let the alcohol drip onto the good caulking.

      Step 5

      Replace the caulk with polyurethane sealant or silicone caulk using a caulking gun. Polyurethane sealant and silicone caulk are available in home improvement and hardware stores.

      Step 6

      Use silicone rubber on cracks at the edges of the window. Silicone rubber will stop leaks from small flaws and will be covered up once the trim is put back into place.

      Step 7

      Press the trim back into place all around the edge of the window. As long as the trim was not bent during removal, it should be easy to push back into the ridge.




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This is a major problem especially to those car windows without a frame. Due to heat the rubber becomes brittle and it cause leakage in windows.

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