From Lotus Internet List

From: "Glyn Harper" <glyn.harper@transerve.com>

Subject: Esprit Windscreen Drama

Date: Thu, 31 Dec 1998 18:55:54 -0000

On Boxing day, the U.K. suffered force 11 winds (well at least here on the Isle of Man we did) and as a result, a slate decided to uplift itself, and try and go for a ride through the windscreen of my Esprit.. To cut a long story short, Autoglass who are going to replace the screen reckon it's going to cost about £1000 and they are going to have to fly someone in from England especially to change it, as the body moves on an Esprit when the windscreen is removed, and special jigs are required. Luckily, it's only going to cost me £40 which is my windscreen insurance excess, and as I have my No claims discount protected, it's not going to have a knock on effect next year. Good job it didn't hit any of the bodywork, I have a £200 excess on that..

From: "Steve" <timelord@compex.ie>

Subject: Esprit windscreen replace

Date: Sat, 2 Jan 1999 13:12:11 -0000

I just read a post from Glyn Harper, about his Esprit which needs an windscreen replacement and the were words like "special jig needed" and "the body moves" mentioned. Now I have an 83 S3 which has a cracked windscreen and I about to get it replaced with AutoGlass here in Ireland. I wondering now should I check to make sure they have the "Jig" (or the Reel :) and expertise to do the job first, (they did say it would take a full day). Any suggestions. Is this a normal windscreen replace method for some cars?

From: "Peter M. Blackford" <pmbsab@naples.infi.net>

Subject: Re: Esprit windscreen replace (E)

Date: Sun, 03 Jan 1999 07:53:05 -0500

Well, when I did the screen in the S2 several years ago, I simply made sure the car was on a flat garage floor and had no problems, then or in the interim. Of course, I know the newer cars have seen great weight-reductions and may not have the structural integrity of the older ones... ;-) I _do_ recall one of the "unanticipated expense" items was replacing the extruded aluminum surround bits, which were not reusable once removed - but the mounting may be entirely different on the newer models...

From: Lorne Mason <l.mason@dial.pipex.com>

Subject: Re: Esprit windscreen replace

Date: Sun, 03 Jan 1999 06:07:58 +0000

When Autoglass did mine there was no mention of a jig being required and I have never heard of the body flexing without the windscreen. I would be surprised if the Esprit relied upon the windscreen for rigidity. The day is required as the screen is glued in place and presumably the glue takes time to dry. Also I can imagine that the old screen must be a sod to unglue and remove.

From: Lorne Mason <l.mason@dial.pipex.com>

Subject: Re: Esprit Windscreen Drama

Date: Sun, 03 Jan 1999 06:01:46 +0000

When I had an Esprit I managed to crack my windscreen with a 100W portable lamp which I was using in the car as i was working in and around the dash! Boy was I pissed off! But I had windscreen cover like you and drove to Autoglass who did the job in a day or two.

From: "Peter M. Blackford" <pmbsab@naples.infi.net>

Subject: Re: Esprit windscreen replace

Date: Mon, 04 Jan 1999 05:28:40 -0500

The "ungluing" part is rather easy: There's an embedded wire in the mounting, which you simply hook to the battery, and it melts/softens the mounting goop for easy removal...

From: "Peter M. Blackford" <pmbsab@naples.infi.net>

Subject: Re: Esprit windscreen replace

Date: Mon, 04 Jan 1999 19:51:10 -0500

The best answer I can give you is "where the manual said they'd be", since I forget exactly where they were... and the manual isn't at hand at the moment.... you_do_ have a manual, right?

What, just keeping it in the car didn't keep the windscreen from breaking? ;-()

From: OggieRobt@aol.com

Subject: Re: Esprit windscreen replace

Date: Mon, 4 Jan 1999 20:05:40 EST

Most modern closed cars rely on the windscreen for structural rigidity. If you consider the car's structure as a box, it's easy to visualise why cutting a huge hole in the forward face will degrade the rigidity by a large amount. This is true even for an Esprit, which gets much of its stiffness from the backbone frame. This is why windscreens are glued in place these days, not just retained by a rubber seal like olden times.

From: OggieRobt@aol.com

Subject: Re: Esprit windscreen replace

Date: Sat, 9 Jan 1999 21:52:52 EST

I doubt that the windscreens are glued in with structural strength glue, and you could probably got more strength by the old method. New style windows are placed in a "ledge" with clearance around the edges to allow for thermal expansion/contraction. The old rubber seal style filled in the gaps (tightly) with the window and the rubber - there is *no* play (although the rubber could compress to allow for thermal effects).

<<The real reason for the flush/glued in windscreens is aerodynamics. The old rubber seal and trim strip was very bad aerodynamically, whereas the flush, glued in windscreens (side windows too) are very good aerodynamically. It's also probably easier and cheaper to glue in the windows than the old way... >>

Not wanting to let it lapse, here is my response to a response:

I'll agree with the cost aspect, but not with the historical part - you're theoretically right about glued windscreens offering the opportunity for better aerodynamic effect, but I think this was largely a fortunate side-effect, not the main reason. Audi made a big fuss about flush glazing when they introduced the 100 as a leader in aerodynamics, but this was mainly focussed on the innovative methods used to achieve flushness in the side glass. In any case, this was several years after glued winscreens became common. For example, the TR7 used the glue method for structural reasons and not for aero benefits. I suspect there were no aero benefits because it was not aerodynamically "clean" ahead of the windscreen. I believe the same would apply to most Lotus cars, which are unlikely to have the same minute attention to aerodynamic purity as the Audi enjoyed. In citing "structural" gains from gluing, it is certainly true that these gains include the US Windshield Retention regulation, as Peter pointed out. This will be even more important for cars with passenger airbags, which tend to react the bag loads into the screen and header area. In my experience, any and all of the glues used to secure windshields are capable of transmitting load from glass to surround - thereby enhancing the structural stiffness of the assembly. Glue does this much more effectively than a rubber surround, since it can exert (and transmit) force in all directions. A rubber surround will only contribute a useful force if the clearance between glass and body is both very small, and very consistent. This leads to what may have been the main attraction to Lotus and other manufacturers - the glue method requires much less critical dimensions of the body and surround, since you effectively lay the glass on top, allow the glue to fill in the gaps, and apply a finisher to cover any errors. It also makes the overall thickness of the surround material less important - very attractive in a panel made of hand-laid fibreglass. To get back to the original question, I think that a new windscreen could be successfully fitted to an Esprit as long as the car is standing in a stable position on a level surface throughout the process. When the old screen is removed some stiffness will be lost, but as long as the body isn't subjected to great twist or bending loads as the glue cures, I'd expect it to regain its stiffness and shape at the end of the process. It may be best to have it standing on its wheels, not on jackstands, to ensure that the static loads are applied in a realistic manner. I'd check the match of glass to body before applying glue - if there is an obvious mismatch, it might be worth looking at means of squaring one to the other before glueing - eg, fiddling with body to chassis attachments. (On the other hand, you could preload the chassis by jacking, then fit the screen and use it as a "pre-stressed" member - it could be beneficial to ride and / or handling, if only in one direction.....but it may get a bit experimental !)

From: "Glyn Harper" <glyn.harper@transerve.com>

Subject: Esprit windscreen. Final result

Date: Mon, 11 Jan 1999 09:39:48 -0000

Well my windscreen has been changed!

Apparently after all the moaning and worrying by Autoglass, they say it was a piece of cake!

Sadly, I was working, so couldn't be there to watch, but it is a nice job. (Well, it's the same as the original screen but not cracked). The bill was £560.. Not too bad. There was a 30% discount for some reason. Not sure what.

The guy did say that to change the windscreen on my 88 Turbo (what they class as an S4!!) is a piece of cake compared to the S3.. (sorry Dean!) Probably down to these bits of metal they stick all over the S3 windows I guess.

So there you go.. Fear not S4 owners. Your windscreens are 'plug and play' compatible.

From: zigglu@us.ibm.com

Subject: Re: Esprit windscreen replace - need help

Date: Mon, 11 Jan 1999 10:40:01 -0500

I am looking at replacement of cracked front windshield on 1977 Esprit. The replacement windows trims are a bit to expensive to ruin. Is there a way to remove and re-use the trim pieces?

From: "Peter M. Blackford" <pmbsab@naples.infi.net>

Subject: Re: Esprit windscreen replace - need help

Date: Mon, 11 Jan 1999 19:49:33 -0500

Sorry Zig, not that I know of... The little grippy thingies hang onto the trim very tightly, so it's virtually impossible to remove it without some bending... when it bends, the soft aluminum stretches & looks ugly in a hurry...

I found mine at http://www.rdent.com , and Ray shipped 'em in a VERY stout tube to prevent transit damage... looks great now! (as you know, it's 3 pieces / 3 part numbers...)