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MG MGB Technical - Windscreen frame sealant

I'm in the process of replacing the windscreen in my 72 roadster due to a crack that started in the top right corner, the shame of is it’s a Triplex with no other marks or scratches. It looks like a stress crack caused, or at least exacerbated by, our third world pot holed roads.

My question is what is or what’s the modern equivalent of the grey non setting sealant used by the factory? I'm not a lover of silicone sealants and would prefer something non setting similar to the original, at least that way I’ll be able to get it apart next time.

Just to be clear, the sealant I'm looking for is inside the frame and seals the joints.

Bob
R.A Davis

Bob I always use Body Line windscreen sealer, it comes in a 310ml cartridge, and out of all the ones I have tried I have found this one the best, it has printed on the cartridge for professional use only, so you may have to get one from your local paint/body shop supplier, or see if a body shop will sell you some, two things I would recommend is, don't seal the frame to the body until its fitted in, as if you do you will get sealer everywhere, and buy all new screws that hold the frame together
Andy Tilney

Bob, before you fit the new screen, check the length of the top screws. The last screen, replaced by "a specialist", lasted 30 minutes because no-one had taken the trouble to measured, a screw contacted the screen edge and after 30 minutes of standing (no 3rd world roads involved) it cracked from top to bottom!! They got a new screen and insisted I installed the screws.
Arbomast is my sealant of choice.
Allan Reeling

Andy

Thanks for the suggestion, I've ordered a tube. It would appear I do have a reasonably local supplier but I can’t get there until next weekend.

I have another question which I suspect may not have an answer. I replaced most of the rubber around the windscreen a good number of years ago when I had some paintwork done. It’s survived reasonably well with one notable exception, the pillar to body seals, the Y shaped seals that fit over the pillar spigot where it goes into the body. These started to fail shortly after I fitted them, the front edges of the seals started to crack and the only way I can describe their appearance is frilly.

I know everyone complains about poor quality rubber these days but I wonder if anyone has found a treatment that might preserve them a bit longer this time.

Bob
R.A Davis

Allan

Thanks for the suggestion, Arbomast looks like a similar product to the one Andy suggested.

Regarding screw lengths, I was aware of this potential problem and I check them all before assembly. I ordered new screws for the top, forgetting the 4 very short screws at the bottom, I had some spares so I’ve cut some to length. The four at the bottom very the only ones that showed signs of corrosion although they did come out reasonably easily. I would have preferred to use stainless screws but the BPZ ones should do the job albeit there’s an unplated edge where I’ve cut them but a dab of grease should help.

Bob
R.A Davis

Bob, As for the pillar seals. Mine went exactly the same way. I've just stuck to repairing them with PU/Sycofles/Tiger seal or similar.
Rubber product!!!**** Hell, if condoms were made to the same standard we'd have to find another planet!!!***
Allan Reeling

This thread was discussed between 29/04/2017 and 01/05/2017

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