2011 BMW Z4

© 2011 National Glass Association. All rights reserved. Visit GlassMagazine.com for glass removal and replacement instructions for more than 450 vehicles. To sign up to receive the For Technicians Only e-bulletin, email FTO@glass.org.

Vehicle type: Two-door convertible

NAGS numbers*: Windshield part numbers FW3112, top bracket, and FW3113, top bracket, rain sensor

Helpful tools or supplies: The condensation sensor is held in place with an adhesive pad that cannot be removed and re-used, so have a replacement condensation sensor on hand. Also have a cold knife or wire available to cut out the windshield.

Watch for:  NAGS warns that you might require a new molding for this windshield, but no new molding is necessary. The underside cowl panel retainers can break easily, however.

*With permission from National Auto Glass Specifications. Call NAGS at 800/551-4012 or visit http://glass.mitchell.com/.

A. Windshield

Preparation

1. Cover the front seats, floorboards, dash and steering wheel with a clean drop cloth or disposable plastic covers. Note: Always wear eye and hand protection when working with glass. Make sure you have the right glass and moldings and that the urethane systems you are about to use are current. Although NAGS warns that you might require a new molding for this windshield, that is incorrect. No new molding is necessary. Windshield part numbers are FW3112 and FW3113.

2. Drape the fender with a fender cover and tape up any vulnerable areas on the vehicle to protect against possible damage. Tape up the defroster vents to prevent debris from falling into the openings.

3. The rearview mirror, rain sensor, condensation sensor and GPS bracket are all concealed by a decorative cover and top header garnish molding. You must remove the interior moldings to disconnect the wiring harnesses. To do so:

• Remove the decorative cover from behind the mirror using a pick or flat-bladed pocket screwdriver to separate the two pieces.
• Remove the two sun visors using a 25T Torx screwdriver.  There are two screws in each visor.  Set aside.
• You can now release the top header and two A-pillar garnish moldings to facilitate disconnection of the two wiring connectors.  There are no hidden retainers behind the moldings; they just separate from the frame, so it’s an easy process.
  
• Use a small, bladed pocket screwdriver to carefully peel the condensation sensor from the glass under the rain sensor. It is held in place with an adhesive pad that cannot be removed and re-used, so have a replacement condensation sensor on hand. Let this hang, or disconnect it and set it aside.
  
• To release the rain sensor from its lens, slide the two side retaining clips downward and separate them from the lens that comes pre-mounted to the glass.  Let the sensor hang, or disconnect it and set aside.
  
• Remove the rearview mirror by giving it a quarter-turn. Let the mirror hang, or disconnect it and set it aside.  Disconnecting the mirror will not require dealer recalibration.
• There is a bracket attached to the glass just above the mirror bracket and the rain sensor lens that houses the GPS antenna.  Remove the GPS antenna from its mounting and let it hang, or disconnect it and set aside.
  

4. Remove the windshield-wiper nut covers.

5. Remove the windshield-wiper nuts using a 16-millimeter wrench or socket.

6. Remove the four push-in retainers at the leading edge of the cowl panel and the two at the corners.  The cowl panel retainer receptacles are a little brittle, so take care not to damage them when removing the retainers.

7. Under the cowl panel near the glass are eight hidden underside retainers that must be carefully released to avoid damaging the retainer receptacles. 

8. Pull the cowl panel and set aside.       

9. Although at first glance it looks like you can cut out the glass without removing the side moldings, you must remove the A-pillar reveal moldings to cut out the glass. To do so:

• Remove the door/glass weatherstrip from bottom to top.  Do not remove the weatherstrip from the top retainer, just the sides.
• Under the door/glass weatherstrip is another rubberlike weatherstrip that is peeled back to reveal three 25T Torx screws that hold the underside of the side moldings. Remove these screws.
  
  
• To remove the side moldings, pry upwards on the molding and release it from the four sandwich-type clips mounted to the wall of the pinchweld.
  

10. Before beginning windshield removal, verify the new windshield is the correct one and the urethanes and primers are current. Never use outdated products as this could jeopardize the structural integrity of the vehicle and the safety of its passengers. Note, the top of the windshield is exposed and close to the top weatherstrip to accommodate the convertible top, but it is far enough away to allow for cutout.

Removal

11. Make sure cutting blades are sufficiently sharp.

12. Before cutting out the windshield, remove contaminants from the glass and pinchweld to prevent contact with the urethane.

13. Use a cold knife or wire to cut out the glass.  The top and sides have plenty of clearance to allow the cold knife blade to be pulled through without damage to the top weatherstrip. To be on the safe side, tape it up anyway to protect against damage.  

14. The top and sides have a thin bead of urethane, but it is slightly recessed and could require an extra-long blade.  The bottom has a thick bead of urethane that is difficult to cut through. The glass is quite curved, so the bottom corners hold tightly. Cut out the corners first to make the rest of the cutout easier.

15. Take the windshield out of the opening using vacuum cups. Make sure the vacuum cups do not overlap a crack in the glass. Lift the glass and place it on a windshield stand or suitable workstation.

Installation

16. After cutting the windshield out, remove contaminants such as dirt, moisture and debris from the pinchweld. Clean the dashboard.

17. If you choose to dry fit the new glass to the opening, remember that there is no gravity stop for the glass, so take care when setting the glass. Mark your glass using a grease pencil or retention molding tape.

 18. Place your vacuum cups on the new windshield in the appropriate location.

 19. Set the windshield onto the old urethane.

 20. With the windshield resting in the opening, make sure it is in the right spot. Adjust both sides to the correct setting, marking the passenger side, then the driver side. Lift the glass and place it on a windshield stand or suitable workstation.

 21. Follow the urethane manufacturer’s recommendations for installation.

 22. Clean the inside of the windshield using a urethane manufacturer-recommended product. Do not touch the bonding area of the windshield after cleaning, prepping or priming it.

23. Wear powder-free Nitrile gloves to protect against harsh chemicals.

 24. Apply the glass prep and primer following the urethane manufacturer’s recommendations.

 25. Using the tool of your choice, remove the original urethane bead, leaving 1 mm-2 mm of existing urethane on the pinchweld. Make sure there are no contaminants and do not touch the pinchweld after you have prepped the area.

 26. Apply the pinchweld primer only to the areas where needed, and follow the urethane manufacturer’s recommendations. Allow preps and primers to dry as recommended by the urethane manufacturer.

 27. Apply a triangular bead of urethane to the same path as the freshly cut urethane on the pinchweld. Before cutting your V-notch, cut the tip off of your nozzle with a nozzle-cutter. With the cut nozzle, measure to the top of the roofline, and at 1/16-inch higher than the roofline, make a mark on the nozzle with a pen or marker. Notch the nozzle up to the marked line; this will give you the appropriate triangular bead.

 28. Lift the windshield from the windshield stand or workstation using vacuum cups. Set the windshield on the urethane at the mark you made during your dry fit. Lower the driver’s side of the windshield onto the urethane and line it up with the dry-fit mark; it is now in place.

 29. The windshield is now ready to be decked. Press firmly to ensure a good seal. Tape the glass to the top weatherstrip to act as a gravity stop.

 30. Before re-installing the parts, check for leaks. Use a leak detector to go over the perimeter of the windshield. If you find a leak, apply more pressure or add more urethane to the spot and ensure that the glass makes contact with the wet urethane.

 31. Re-install the removed parts in reverse order. Remember that the top header and the top of the interior A-pillar moldings snap above the window frame and below the top lip of the weatherstrip.

 32. Allow the urethane to cure according to the urethane manufacturer’s recommended cure time before returning the vehicle to the customer. Warning: Disregarding the safe drive-away time that your urethane manufacturer recommends could jeopardize the structural integrity of the vehicle and the safety of its passengers.

 33. You have completed the removal and replacement of the windshield.

© 2011 National Glass Association. All rights reserved. Visit GlassMagazine.com for glass removal and replacement instructions for more than 450 vehicles. To sign up to receive the For Technicians Only e-bulletin, email FTO@glass.org.