[xk8] Elimination of XK8 Windshield Demister Vent Rattles 

Another project by Dan Jensen

Recently, both the drivers-side and passenger-side
windshield (windscreen) demister grills in my ’01 XK8 (65K
miles) developed very annoying buzzy rattles. I could reach
up and stop a rattle, but it would soon return when driving
over rough patches in the road. I was fairly certain that
the rattles resulted from the demister grills vibrating
against the windshield. Sanford Lindstrom solved a similar
problem by inserting a rubber gasket between the windshield
and grills.

I decided to determine what was causing the problem before I
embarked on this approach. The attached photos show the
result of what I found.

In short, the glue that holds the metal tabs securing the
front edge of the grills had failed. With a simple
application of epoxy, I was able to return the metal tabs to
their proper position, which brought the grills back down
against the dash and away from the windshield. The result:
no rattles and no evidence of a repair. Cost: ~$0.25 of
epoxy and a couple of hours of my time.

Left-side window demister grill as seen from above through the windshield.  Both the driver-side and passenger-side grills developed buzzy rattles that grew steadily more annoying.

A plastic paint scrapper being used to press the four plastic retaining tabs on the rear of the grill forward, one at a time. They were stiff so be patient.

Double-stick adhesive strips that were apparently meant to help hold the grill in place, or at least lessen the chance for rattles. They were dried and non-functional.

Underside view of the demister grill. One of the four plastic tabs can be seen, along with one of four slots where the dash-mounted metal tabs hold the leading edge of the grill in place.

View of leading edge of dash with demister grill removed. The strips holding the metal tabs have pulled free from the supporting base due to failure of the glue (seen as yellow deposits). High temperature in this area probably contributes to glue failure.

Closeup view of the two surfaces after applying the epoxy. Again, not pretty, but functional and unobservable.

Rags used to hold the surfaces in contact. I pushed the rags in place with the plastic scrapper, making sure that there was very tight contact. I let the epoxy cure overnight with the rags in place.

View of surfaces after epoxy had cured. The metal tabs are now in their original position. I reinstalled the demister grills, again being patient since this required a fair amount of effort. I wore gloves and used the plastic scrapper.