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MG MGF Technical - Windscreen replacement

My MOT is coming up and I'm going to need a new windscreen. The original one has, over the last year of little use, developed a 20cm crack starting at the frame at the bottom of the screen, directly in line with the steering wheel (LHD). it progresses up about 2cm and then turns right for the remainder of the crack.

Anyone else had this problem, or had a screen replaced? (note that this will not be an insurance job, so advice of good value options is welcomed!)

N837 OGF


Why not an insurance job? Most UK insurers have the glass as a 'no loss to your no claims job'.

However I remember some time back being told by someone at Rover that the windscreen forms a part of the structural strength of the car - SO - the car should not be used for at least 24 hours after screen replacement to allow the bonding agents to fully set.

Ted Newman


Have taken a stone in my windscreen this summer just in front of the wheel (LHD). The dealer just take my car for half a day. I've not wait for the glue to stick or whatever your dealer say.

The works is quite long for a windscreen replacement (3 hours). They have to take the windscreen off by cutting the glue, then stick the new one.

In france the cost for the windscreen is aprox 1400 FF so it 150 pounds (inc tax) + 1200 FF (125 pounds) for the glue kit + works (3 hours).

When they give you the car back watch :

- Around the windscreen. As they cut the glue they can touch the paint around. They ve done it to my car and I ask them to repaint the frame (accepted).

- On the bonnet. Indeed they could have made trace on it so watch out closely in the sun.

- Inside the cable for the mirror is well fitted in the frame garnement.


Your right Ted most car windscreens are bonded in ,first done to reduce costs on production line easier for man/robot and quicker to fit than screen/rubber surround/trim fillets.
If not paying on insurance ring round local smaller companies and tell them its cash/cheque you should find a good deal.
Mabonnet is also right old screen will be either cut out using a cold or hot method and if fitter is not V/careful can damage surround.

>>>>I remember some time back being told by someone at Rover that the windscreen forms a part of the structural strength of the car

That doesn't say much for the structural strength of the car, does it! I've just fitted a glass rear axle too. :)
David Bainbridge


I am sorry you think I am talking a load of crap and I am equally sorry you find it requires rudeness and agression to reply.

AND BTW it was not what 'my dealer' told me but as I said what Rover told me AND they told me that when visiting their factory at Longbridge and watching them assemble MGFs.....BUT OF COURSE if Maxime knows better who are we to take notice of what the Manufacturer tells us.

And for more detail what they said was:- The strength of the MGF is enhanced by having a re-inforced windscreen surround and the windscreen is bonded to the surround and contibutes to this strength and if for any reason you have the screen replaced ALWAYS give it 24 hours to set before using the car again.

And the reason for this special attention to the windscreen is because the car does not have a 'tin top' to keep the body rigid and whilst you may not see it the car will flex AND if the windscreen bonding is not fully set then this area will not be as regid as it should be.

Me I am more likely to take Rovers advice than some French dealer/repairer/bodger.

Ted Newman


I take it your remark was supposed to be funny as you put the :-) sign afterwards but I can assure you that glass can be extremely strong used the correct way but I am nut sure that a glass rear axle would be useful especially as the MGF does not actually have a rear axle, it has independat suspension with the drive being transferred by 'drive shafts'.

Ted Newman

>>>I take it your remark was supposed to be funny as you put the :-) sign afterwards

Er, yes it was. Maybe it failed. :(
David Bainbridge

>>I am equally sorry you find it requires rudeness and agression to reply
Ted, knowing Maxime from "Le Forum des Francophones", I presume he didn't want to be rude in his reply. This is (I suppose) due to a tactless use of English words (the same words are not necessarily as rude once translated in French). I'm sure Max will confirm.

Anyway, I can't comment on the substance of his thoughts but I assume it's a problem of form.

Best regards ;-)

I had a similar crack on my windscreen some time ago. It started from a minute stone chip in the centre of the screen at the bottom and spread from it towards the driver side without me noticing.

If I remember correctly the decker panel(?) (the bit of plastic that goes across the width of the car through which the windscreen wiper mechanism passes) has a hook on it. The hook has to go under the bottom of the windscreen otherwise the panel will not sit flush. Not all windscreen replacers are aware of this fact. The windscreen also has a notch in the bottom on one side, where the hook passes underneath. I don't know if the lefthand drive cars have the notch and hook on the opposite side.


Having read the statement I do not think that Maxime was being rude- rather he makes an exclamation that he's had a damaged windscreen- and if I read it correctly, having been some potentially poor service from his dealership... (?)

Having a bad day Ted?

Regarding glass in the suspension- I agree- I've heard that some leaf springs are made from glass fibre re-enforced plastic... its tough stuff where forces are placing the material under compression and extension. Not so clever under bending stress
Rob Bell

Let me finish the last statement...

Not so clever under bending stress I suspect.

Bloomin' keyboard!
Rob Bell

<<due to a tactless use of English words (the same words are not necessarily as rude once translated in French>>

I think bollocks pretty clear any language unless it should be testicules or boules:-)

OK Ralph, but I would have said "Couilles" ;-)
What do you think of "Rubbish"? Is this more an appropriate word
Hey Max, where are you, the guys need some clarifications here!

When some one ask a question I try to answer that question, if I can, and if I have some information that I think may be relavent I will mention that.

If people disagree with me then that is fine, that is their entitlement, BUT when they start their statement (immediately after my posting) with the word BOLLOCKS !!! - I take it that they are adressing me, and in rude and agressive fashion.

I am sorry Rob but no I am not having a bad day I just dont like people shouting bollocks at me - there was absolutely no excuse for it - even if it is not your native language.

And as a BTW I stand by my statement regarding the the glass being a part of the body stiffening.

Ted Newman

Les bollocks?
David Bainbridge


Back to Le Thread,
Watch out that they don't break the plastic moulding in front of the windscreen or scratch the screw covers in it. They did on mine.

Bruce Caldwell

hey hey hey, calm down everybody...

First on this bollock think... Yes I'm not native english speaker but I have no excuse because I used to live in england. TED, it was not an insult aimed at you... It was just saying that when I change my windscreen, I just take my car back without waiting 24H. In france if you want to tell the fact that you're worry about something just say "Les boules" whitch can be translate by "Bollocks". But it's humoristic... Nevermind. I appologie about the misunderstanding.

Second, I would like to ligh the fact that people get really nervous on this BBS. If a word goes wrong it became really quickly a mess. Where is the sense of humor we had on this BBS before? Pehars the numerous threads from people who just want to troll make it desappear...

Thrid about this rigidity thing. I tought about it and what the rover guy told seems strange to me. Indeed the main problem for waiting 24H is the fact that the glue is not stick correctly. But generaly those glues stick in less than an hour (have seen it, in my garage). Moreover if the glue is not properly stick then the main problem will be the fact that the windscreen should unglue and not cracking. So I don't see the point for such statement but as you say TED I'm not a mecanical and I'm not from rover (and I'm french) so I should just shut up and don't try to understand...



>>and I'm french
Nobody's perfect ;-)


OK mate sorry I was a bit upety!

Tonight I will see if I can find the transcripts for the Longbridge visit because I am sure it was in there about it!

Ted Newman

Just to add my twopenn'th, when I had my screen replaced I was told not to drive the car for 24 hours. The guy also suggested that I park my car the other way round in my driveway, but that's another story. ;)


Just quoting from the workshop manual:

CAUTION: A curing time of 6 hours is desirable, during this time leave a window open and do not slam the doors. If the car must be used, drive slowly.

Spyros Papageorghiou


To answer your question, I have classic car insurance on my F (the difference between 300GBP pa and 1000GBP for London). Glass cover isn't included. (D'oh!)

Amazing how threads can go from windscreens to genitals in 24 hrs....

Anyone had a windscreen replaced by a non-Rover source? Autoglass for instance?

BTW, glass can be incredibly tough. Bullet proof if you're willing to pay enough. But it's difficult to make it fatigue-resistant, hence its limited use as axles (or half-shafts).

N837 OGF


Hugh, mine was replace by Silverscreen on my insurance policy. They used an MG windscreen, however I believe that some windscreen replacement companies use non-MG screens.



I have a replacement windscreen from AutoWindscreens and I wouldn't let them near my car again. As Bruce suggested they can damage plastic moulding at the base (or actually break it), damage the screw covers and strip the thread on the fixings. Also the AutoWindcreens logo obscures the tax. Otherwise no complaints!

Not true, the rubber seal has come away from the top corners.

Neil Stothert

>>>CAUTION: A curing time of 6 hours is desirable, during this time leave a window open and do not slam the doors. If the car must be used, drive slowly.<<< there is a prior curing time for the bonding agent prior to the fitting of the new glass. I have no idea how long this should be.

Roger Parker

I had to replace the screen after just a few weeks from new - crack originated from stone thrown up on M-way. Insurance covered except for £50 excess. However the screen RAC Windscreeens turned up with was emblazoned with RAC logos. I rejected that and asked for OE one. They were happy to order one from MG Rover Dealer and fitted it a couple of days later at work. No damage to car whatsoever. Excellent service and they kept in touch re order progress and fitment arangements. The fitter requested I didn't drive for a minimum of two hours, leave window open (to ensure pressure equalisation whilst curing) dont slam doors etc. I left anyway for some 5 hours.

WRT the comments about screen contributing to structural strength of the car that would be 'technically correct'. Anything attached to (or removed from) the structure becomes part (or not part) of that structure and stress, strain, load paths characteristics etc are modified to a greater or lesser extent. I guess the question is one of degree. A sheet of thick steel welded into the screen frame would add significant ridgidity to the frame (not much good for driving though - although around here I'm sure some folk have these fitted...). A glass screen held firmly adds some ridgidity, but stuck in less so. All in all, it has some effect but I doubt whether it is mechanically significant. I understand the screen frame was designed to support the weight of the car (some roll over protection) and I know of a crash where the frame prevented the occupants from being impaled by a m-way central reservation crash barrier. Not pretty result but effective.

Incidentally, glass based materials are used in structurally more demanding applications than cars; aerospace for example. Also adhesives are widely used in similar high tech applications. So if you want it to be structural its possible but I doubt the MGF screen is structurally significant sitting as it does on plastic locators and a bed of compliant adhesive (thus allowing flex and movement to prevent stress cracking). I supect the cure time and keeping screen still stuff is more about movement and preventing possible leaks than having a floppy MGF without it.

This thread was discussed between 24/10/2001 and 28/10/2001

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