Hi-Temp Silicone Sealant Question. You Brickies Maybe Able To Help

[a98pmalcolm]

Its kind of a Supra topic question but kind of not lol..

 

Recently I solved an issues with a misting headlight. The solution was to scoop out with a knife the old sealant that had gone soft to cause moisture to get in. I used normal black silicone sealant and really pushed it into the gaps making a nice seal.

 

A few months have past and all was good until the other day. I noticed misting in the headlight again (even in the high heat were getting) Back to were I was..

 

So I popped the bonnet and had a good look around the headlight and noticed the sealant was all gooey and wasn't like sealant should be.

So I have come up with the conclusion with the recent heat we have had and engine temps the sealant has somewhat melted and softened.

 

So my question what is a good black high temp resistant sealant on the market. There's a few out there and it all seems reasonably priced.

 

Thanks

Paul

[paulj1]

I've used this Ct1 adhesive and it bonds itself back together if split

[Konrad]

http://www.ebay.co.uk/itm/like/291080816790?limghlpsr=true&hlpv=2&ops=true&viphx=1&hlpht=true&lpid=108&device=c&adtype=pla&crdt=0&ff3=1&ff11=ICEP3.0.0&ff12=67&ff13=80&ff14=108&ff19=0

I was using Tiger sealant black to seal all my headlights after refurb (and i've done 5 pairs already) none of them never misted. I was splitting lenses from body, then clean seal area where there was excess of old sealant, then I was filling it with Tiger seal and put all in owen to heat all up (oven set to 100C) with lens just loosely sitting on the body. Once hot, I pushed lens properly and smear excess around connection line (use baking gloves when pushing it!)

You can also clean and respray plastic covers inside when you are on it. I used matt black spray after sanding rings out(they was peeling) and I took out triangular metal cover from underneath of middle lens for spraying duration and put it back once all is dry - looks nicer imho.

Edited July 14, 2014 by Konrad (see edit history)

[a98pmalcolm]

i don't need to split the lights. it's only to run a seal around where the lights split apart. so maybe run tiger seal around instead of the silicone sealant do you think that would be more efficient

[dazla100]

when i took my headlights apart i managed to reseal them with gasket sealant and not had a problem with them at all think normal silicon wont work especially on a hot day hope this helps.

[MC_Bob]

Remember to check your breathers are working. When lamps cool they'll pull in moisture from the small porous points if the little filter thing is blocked.

[a98pmalcolm]

Cheers guys

 

The headlights clear up over night, so it appears when the engine is on its steaming up. Going out to find tiger sealant today. will update you all

[SupraP-Z]

As above, check the breathers mate. IIRC I removed mine and they hardly ever mist up. I also used gasket sealant to seal mine, very rarely do they actually mist

[Mk4Gaz]

The problem with sikaflex or tiger seal, is that if you ever have to get them back apart, it could cause you major trouble.

 

I've read that using windscreen sealant is good, because it stays slightly flexible, so will allow for expansion with the plastic. It also should stand up to the engine bay temperature around that area.