Exhaust Sealant

[hengti 2]

after some recommendations, as topic title. i'm struggling to seal an exhaust and am wondering if any 'wonder sealants' exist. i've had a go with copper grease and a couple of these paste type sealants and it's still leaking.

 

is that my lot, or is there anything else i could try?

 

any suggestions gratefully received. thanks

[mickie 3]

is the exhaust manifold and cylinder face flat ? and are you using a steel gasket ? didnt think you were supposed to seal exhaust gaskets up with bodge

[hengti 2]

sorry, should have said; they're both system joints after the CAT

[mickie 3]

sealants arent very good at sealing big holes, cracks or anything like that, also depends how you're applying it, pull the exhaust apart, apply paste sealant and put it back together, stick the clamp on and run the engine to harden the sealant..

 

would normally work unless theres something wrong with the exhaust

[hengti 2]

thanks for the thoughts.

 

thinking on, there are actually three joints - one is a gasket flange (the face of one of the surfaces is pitted by corrosion, which i'm assuming is causing the problem) and the other two are pipe sleeves (no deformation of pipes; they're clean and a good, tight fit).

 

i don't really like using pastes as they make taking everything apart again difficult and are a pain to clean up after, but have had to. not sure why they're still leaking as you'd think they'd now be OK, but would still appear to be a problem.

 

was wondering if anything other than these pastes is available - ?

Edited September 13, 2008 by hengti

[Tom Fenton 1,542]

I've never tried it myself, but a good mate whose judgement I trust reckons silicone sealant works a treat on problem joints that exhaust paste won't seal.

[nick9one1 2]

I would have thought the exhaust got too hot for silicone sealant?

[jimistdt 1]

Apparantley Silicone has a working temperature range of -60C ~ 200C, although some are designed specifically for high temp applications, like THIS one

 

 

Jimi

Edited September 13, 2008 by jimistdt

[dcc 855]

rtv sealant is £4 from my local factors, if it doesnt work, your £4 out of pocket.

[hengti 2]

thanks for the replies. as it was suggested, i had a quick search for high temp RTV sealants and have read that some seem to swear by a high temp copper based RTV sealant. it seems expensive for a tiny quantity, but i'll have a search about to see what i can see. thanks again to all

[Tom Fenton 1,542]

In your situation I'd certainly give it a try, as mentioned above if it doesn't work you are £4 down for a tube of goo, or like me you may have some kicking about in the garage anyhow.

[Baz 421]

Loctite copper gasket/sealant '5920'

 

It's THE b*llocks, plain and simple.

[hengti 2]

^ that's actually what i've bought. it says it'll withstand up to 350degC but the pastes are generally rated at 2-3 times that - ?

 

anyway, i'll see how it does once i've the time to be taking the exhaust off and cleaning it up again

[James_R 3]

Used that stuff to seal head to manifold on several engines with no problems, awesome stuff a must in all tool boxes along with threadlok