When Fitting New Exhaust, or Sections

Yes, place your time and money saving tips here.Nothing illegal or dangerous please!Motoring related only please.

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When Fitting New Exhaust, or Sections

Post by G4EIY »

Hi All,
Don't know if this tip has been aired before, but here goes:
When fitting a complete or part exhaust system, I always smear silicon mastic/sealer, (any brand will do the trick) onto all the joints...
Then if in the future it's required to remove, it all comes apart very easily, no rusted or seized connections...

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Post by Louis_vtr »

"I always smear silicon mastic/sealer" is this all you do or do you use an exhaust sealant too?

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Post by G4EIY »

Hi Louis,
I have always only used the silicon/mastic sealer.
Smear on both the mating surfaces of the pipes, this will fill the gap when the clamps are tightened.
I have used this method now for many years, and never had any leaks or problems.

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Post by RichardR »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by G4EIY:</i> I have always only used the silicon/mastic sealer.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Hi Brian,
Presumably this has to be a particular type of silicone sealant to deal with the high temperatures and, if so, where do you normally ge it from?

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Post by G4EIY »

Hi Richard,
As far as I am aware, silicon will tollerate very high temperatures, not sure of the limit, but it cerainly works on car exhausts.
Silicon tubing is also used for the exhausts on model diesel engine exhausts, that's why I tried it...
Any silicon sealer will do, cheapest you can find, my last purchase was from Wickes, two for the price of one, but I suspect that offer has finished.

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Post by Stempy »

Don't get any silicon based product near the lambda sensor as it will kill it.

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Post by drpau »

I suppose its better than exhaust paste as with the sealant there is a bit of give and flexibilty with it whereas with the paste it hardens solid and it more likely to crack. Nice one....

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Post by turbolag »

Don't use a silicone based mastic as it gives off moisture as it cures, which gets trapped in the join by the mastic, which then plays corrosion havoc.
The best thing to do with exhausts is to get the local tyre and exhaust shed to fit it - most do free fitting (so there's no point tring to save cash doing it yerself) on systems and you can still stand there and watch them to ensure it's done properly.

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Post by Kowalski »

I doubt the local Kwiki-Fit will do free fitting on an exhaust I buy from GSF.
"Fit your exhaust sir, certainly, which arm will you be using for payment?"

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Post by citronut »

exhaust centre fiters are on commission so they will try to sell you every thing they have on there shelvess at an extautionat cost,also you must never put any sort of sealer on joints forward of a cat,because it will get into the cat and do a lot of no good regards malcolm

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Post by fastandfurryous »

If anyone does allow kwik-fit to fit an exhaust for them, I would definitely stand and watch them. I once saw a pillock beating the floorpan out of the way with a clubhammer because the exhaust didn't fit properly. Owner knew nothing about it until I told him. I get the feeling he did an awful lot of damage to that car.

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Post by Kowalski »

I had an exhaust fitted to my mother's car which didn't fit, but the guy that did it got out the oxy-propane torch heated it up and bent the exhaust to the shape it should have been made rather than fixing the car.
Customising your car to fit the exhaust seems a bit excessive, what happens if the next exhaust is a different shape too? [;)]

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Post by micitroen »

Just seen the thread and thought I'd add my 3 penn'eth. On a Harley Sportster I had; all the exhaust sections were put together with silicone. At the time I mentioned it to the dealer thinking it was maybe a temp thing 'til the bike was 'run in' and he said that they (Harley Davidson) had been using it for years and never had a problem with it. Obviously it didn't have a 'cat' though.