51 31... Notes on window bonding; work steps for removing and installing window glass: Hardening
The adhesive hardens as it reacts with air humidity (with accelerator also due to mixed-in reaction paste) at room temperature.
Minimum hardening time (table) is obtained from 22°C and 38 % relative air humidity.
A relative humidity of < 30% significantly slows hardening.
At ambient temperatures above 23°C and 50 % relative air humidity (hot countries), the adhesive open time is shortened to approx. 5 minutes (skin formation time).
The adhesive hardening process is interrupted completely at ambient temperatures below 5°C. In this event, there will be no increase in the strength of the bonded connection.
Do not subject the vehicle to load on one side during the minimum hardening time (see table, without front passenger airbag), such as e.g.:
- one wheel on curb
- vehicle hoist
- etc.
Maneuvering inside garage/workshop:
- only permitted on level ground
- do not under any circumstances drive over approach ramps, e.g. into multistory parking structures
Remove adhesive tapes after hardening time.
If you fail to adhere to the minimum hardening times (see table, without front passenger airbag):
- Leaks and/or wind noises may occur at the window glass
Minimum hardening time:
| Adhesive | Minimum hardening time "without front passenger airbag" (after which vehicle can be moved) | Minimum hardening time "with front passenger airbag" (countries where seatbelt use is not required by law) | ||
|---|---|---|---|---|
| Cold processing | 1 hour | 2 hours(1) | ||
The vehicle can be transferred to the customer after a 1-hour hardening time with the following warning: Once the windscreen glass has been bonded, all occupants must travel with their seat belts attached for 1 hour. This is applicable only for countries where seatbelt use is not required by law. |
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Locate leaks:
- by spraying water underneath sealing lips
- with ultrasonic leak detector (sourcing reference: BMW Parts Department)
If necessary, seal leakage with appropriate nozzle.