Oh dear,...
I removed the original sunroof to service/check the mechanisms, and wanted to renew the seal around the glass panel.

On three sides, the glass was no longer bonded to the frame - quite rusty on the metal frame. It was still bonded on the leading edge, and a pain to try and remove. So much so that I broke the glass. Not happy 🙁🙁.

Ordered a replacement, removed the seal and .... it's just the same. It's a real pain to try and get a blade in there. Probably do-able, but I think it will take a couple of hours.

So, does anyone know what the bonding agent is between the sunroof glass panel and its frame, and what the solvent might be? It looks rubber-ish. I tried putting a slice of it into acetone, and thinners and neither of those seem to make much impact on it.

Ta

Body seam sealant should work quite well.

Could it be windscreen bonding/PU adhesive? If it is then they tend to cut it out. Not sure how the bond is done on the sunroof, but would getting a windscreen removal tool like this > https://www.amazon.co.uk/Windscreen-Remover-Rubber-Bonded-Removal/dp/B01MQ2BR58 be any use?

If you are now trying to get the remainder of the sealant of the broken glass off the frame,
I have had very good luck using an electric heat gun to soften cured adhesives and remove them.
Not necessarily a good idea to remove goo from glass you wish to re use as differential heating can cause tempered glass to shatter.......

Thanks guys,

The first one shattered I'm afraid, when I'd got it 85% free.... Leaving me with a rusty metal frame.

Second one (from a breaker) looked better at first, but as soon as the seal came off it was obvious that it was pretty much the same. I'd even be tempted to carefully cut the second frame off and use my original one, but unfortunately the second frame is stronger so I'd prefer to use it if I can.

Brian that tool you linked to looks pretty handy but whatever it is, the stuff is pretty hard. I think it would take some serious effort to pull the blade through. I hoped to get a clue about a solvent to try softening it up first.

I had also thought about heat - but as you say, I don't want to shatter another one!

I called it a day earlier when the blade slipped and put a gash in my thumb - through the glove. Looks like I'll just need to persevere - and keep my hands clear.

Not good, If it is that type of stuff its horrible to remove. It might help to keep the bit indoors where its a bit warmer at present to allow the glue to warm up that way first. Otherwise the other way they tend to tackle the pu glue is with a cheesewire type arrangement. Theres some details in Rave for the other panels (windscreens and rearmost windows) but nothing mentioned about that seal your dealing with. It does show a combination of the tool posted above and the cheesewire method. I'd guess it comes with the metalwork as one piece looking at whats in there.

Theres a few solvents mentioned when you look around for something to remove pu adhesive, but the main one mentioned is Acetone - which you've already tried. So either Acetone isn't going to do it, or its some other type of adhesive.

To be honest, not something I would of tackled, if it was sealed I would of left well alone, I understand tackling rust etc, but I’ve never had any problems with sunroofs on any of the landrovers I’ve owned,, bring back the webasto type, lol

^^^ There's definitely merit in that Chris, I didn't set out to get engaged in an 'epic' - but the key word is 'sealed'.

I'm not 100% sure it would have been. It's apparent that the edge seal around the glass panel (the fabric/rubber and felt one that sits between the glass and the bodywork) was all that was holding the glass to the frame on three sides. The amount of rust between the two shows that a lot of water gets into that location and just sits there.

Given that I've found this with two now, I'd hazard a guess that many will be like that. And then we're back to Chris' advice ... leave it well alone! I'll know 'next time'..

I have been using a pu adhesive/sealant just recently to glue wheel arches on. The sealant I used was Tigerseal.
One of the wheel arch sections slipped down and I had to take it off again as it was glued in the wrong place.

For getting the old stuff off I used a heat gun with a small scraper. The heat gun has a digital temperature readout and I found 250 deg C was effective at softening the sealant without damaging the paintwork. I also found that meths works the best for getting small smudges off the bodywork.
I tried IPA (Isopropyl alcohol, not India Pale Ale!) which works but meths is better. A suggestion on here.
Be careful with acetone. It dissolves some plastics, particularly ABS and might lift the paint.

Thanks Dave,

I'm still drinking my coffee and googling for solutions. Seems like the rusty sunroof frame/glass bonding issue is quite a common issue in many older cars. Found it on Fiat and old Rover forums amongst others.

Heat has been used to split them apparently. I've no worries about acetone or meths affecting paintwork or whatever as the glass is off the car, and in my downstairs 'workshop'

I did find our very own Marty talking about this issue on 'the other side'. He said he'd split the assembly into its component parts and repaired it.

So current plan is to try the heat gun and some plastic wedges... wish me luck!

Just to close this off....

RIP Old sunroof - sorry I brought you to this:

Back to the 'new one' - I tried heat on the back of the frame, and it only made a marginal difference if any in terms of softening the bonding. But to be honest I was probably too gentle with it - I didn't want another glass to split into tiny cubes.

So I was still at it, hacking away, a millimetre at a time and getting frustrated and shouty. My wife upstairs heard me, came down and we both had a go at it. I was still getting grumpy, so I was banished to the outside garage. 20 minutes later she came out with a sunroof frame...!

It turns out, where I was thinking about what suitable things I might have in my toolbox - she was thinking 'kitchen implements' and did the job with a bread knife and an old carving knife..... So you can have heat, and solvents, but "Mk 1 Wife" is the thing to use..!!

Two frames, one sunroof:

Having had the difficult bit done for me, this is what's exposed - you can see why the glass and the frame parted company.

The adhesive was still very firmly attached to the glass, but only bonded to rust around the frame. I think the only reason the leading edge was still attached so strongly is that the strengthening channel on the leading edge doesn't rust, and the bonding sticks to that really strongly.

Ho hum - brushed down and painted with the rust converter. Painted tomorrow.

Having done all this, I'll bond and clamp it and hope for the best - but I think Chris is right when he says if it isn't leaking, don't go here.

Oh wow. Mine had some rust, about the only rust I’ve seen on my P38, but nothing like that!

Harv, I reckon it's thin metal, with only minimal protection. Then, if you imagine driving along a main road here during the 'salty roads' season, you'll be driving through a cloud of salty spray. Some of this must make it onto the sunroof, and underneath the seal, where it doesn't drain well.

Added to that, it's probably a little warmer up there sometimes, either sunshine, or heat from the car. So I reckon there's a pretty toxic combination of factors contributing to this.

I suppose, if it's repainted, and I put a bead of mastic inside the new seal, that mine should now be good for another 5 or 10 years and that ought to be enough.

From your other thread it seems that your car has lived somewhere very damp and/or salty. All the underside had far more rust on it that any other car I've seen so it makes sense that the sunroof frame would also be rusted. I would think it's lived by the sea for most of it's life.

Hi Gd - the information I have from the V5s is that the first owner was in Ripon; 2nd in Durham; and I'm the 3rd. Not to say they didn't keep the car by the marina, or the 2nd cottage in Cornwall, but I don't think so. I suspect the underside rust is just from being that little bit further north = roads salted more often. Though again, at ca 72k when I got it, it hasn't seen as many miles as others.

The fact that my original sunroof, and the one that came from the breaker were exactly the same suggests to me that this is just a more generic issue

donmacn wrote:

And then we're back to Chris' advice ... leave it well alone! I'll know 'next time'..

Something my dad always said, if it works, leave it alone, lol, would be interesting to have one of the frames apart though, luckily I’ve no problems with mine, so it won’t be coming out 😂🤣

You know what they say, if it ain't broke, don't fix it.....