C class rear windscreen repeat shattering

[peter hitchcox]

Can anyone help? Our rear windscreen has shattered for the fifth time. The problem has been checked by a registered dealer. Could it be linked to a faulty rear window heater?

 

[Dieselman]

It sounds more like a body flexing problem to me.
Which body style do you have, saloon or coupe?

Maybe you just have the bass bin turned up a bit too loud..or the neighbours don't like you.

 

[Bobby Dazzler]

Are you able to tell where on the rear screen it's originating from? If so, similar place each time?

 

[Bobby Dazzler]

One thought - and I don't really have any basis for it - is there may be something protruding from the body shell which when the body flexes is placing a concentrated stress on the rear screen - and hence asking if it appears to originate from the same place each time.

That said, one would hope that the fitter would look for something like that, and that the seal would isolate it to some degree?

 

[television]

Or you could have one high point that stresses the window at a certain point.

I would have laid the window against the aperture when it was clean back to metal and no rubber, laid the glass in and check for any high point that could stress the glass

 

[BlackC55]

What are the circumstances of the shatter?

 

[DaveTheDrummer]

What you could do is have a look at the new window, after it's been fitted for a few weeks, using a polarising filter. Some sunglasses are polarisers and you can buy polarising film from Ebay and you may even know someone who has one for a camera lens.
When you look at the window through the filter you'll see rainbow lines in places. You can rotate the filter to get a better view. The lines will be closer together at the points where the stress in the glass is higher than other places. This may reveal somewhere that the glass is under greater stress. You could then look in that area for a possible cause.

 

[Gbrowncls55]

has it ever been in an accident. slightly out of alignment screen frame might just allow the screen to be fitted but push it too far when the body flexes.

 

[Ted]

Thread is 11 years old...