Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Morgan 4/4 Sport Windscreen

Heinz,
I can't see how the missing parts could be retrofitted.It's not just a support for the spare wheel but two complete crossmembers - to be honest it looks a vital part of the frame to me but I have absolutely no expertise in the area of frame design. Still, it would be interesting to hear what the factory think about why so many sport cars suffer windscreen failure.
nick

The +4SS frame is the same as all the Sport models without a spare wheel. Looking at the construction I doubt if the spare wheel crossmember makes much difference to the torsional rigidity and around the windscreen area of the body there is the stainless tubular crossmember which will brace that area.

Doesn't the tubular roll bar under the dash fit to the chassis? I don't know if it ties to the body frame (does it?)
I'm thinking that the body flex (which is already quite alot)might be more without the rear crossmembers thereby causing more twisting.........?
More than happy to be proved wrong.
Nick

I totally agree with Jays.

Adding the crossmemberframe to the back won´t do anything essential for strengthening the cars structure - it´s simply a bolt-in (mind: NOT glued in!) structure for fitment of spare wheel.

Imho most cracked windscreens source to inadequate fitting/erecting of the "old style hood", which is standard on all 4/4 and +4 Sports - and mind: all/most people writing about window cracks have exactly these models!

To start buttoning the hood on the screen and only THEN fixing the rear buttons is the way not to overstress the window(frame) with inadequate tension.
Dismantling starting with the back is better as well.
Even better is adding the hood swivels to the procedure (using them makes it a lot easier and safer for screen & fingernails....)

But all of this is just my own experience and technical understanding (plus the advice of MMC when picking up my car at the factory..)

Aha, I hadn't considered the hood thing. That does sound a likely cause. Seems a better theory than mine. The only thing is why isn't there widespread screen cracking of all models before the "new" hood? I do remember the horror of trying to fit the old hood in the cold; actually I'm amazed I never broke my windscreen then!
Nick

Later/actual windscreens seem to be a lot "weaker" and softer on the surface than former ones, as i have been told.....

Thanks for that I read it on here believe it or not and if I find the thread I'll let them know. Because to have a new laminated screen fitted to the frame for £140 seems reasonable to me. I never bothered much with the heater on the Plus 8 or this one and with the roof off the heated screen is another detail like a radio to me a little superflous.

In my ownership of the +8 I never had a problem when the roof was needed with cracked screens, I just think there is either a manufacturing defect in the screens (most likely) or alignment and fixture of windscreen to the body. We do have +4's on here with cracked screens also.
No one seems to have the real answer but some people and Dealerships are doing "quite nicely thank you" out of the problem.

My Sport is fitted with the same double diagonal roll-bar as the +4SS and it probably removes more body flex than the spare wheel crossmember. An additional benefit of having the roll bar is that it makes hood swivels redundant as the hood is supported by the r.b and can be fastened at front and rear in a non-tensioned state, the tension only being evenly and progressively applied as the hood frame is pulled up from inside the car.

I have a theory that the screens are susceptible to cracking when subjected to rapid changes of air pressure, the screen on my 4/4 Sport cracked when I was stationary in traffic and a large truck coming from the opposite direction swooshed past at 60 mph, the wind blast rocked the car and 1/2 a mile down the road I noticed the start of a crack. A member of the Warks MSCC started his BSA 500 single cylinder motor bike and cracked the screen on his Roadster parked a few feet behind the bike........just a theory, not easy to prove beyond doubt

Yes it would be interesting to establish a few facts on the screens in an attempt to "crack" the problem - doubtless the factory have their own answer which involves them spending money. We won't be likely to hear that one then.
The first question to ask is is it only heated screens that are susceptible and the next has the supplier changed and so forth.
Interesting hearing your story though.
Not as interesting as your "new" Red Roadster though - enjoy