Make a car exhaust system last longer by painting it with something?

[AL_n]

Anyone know of anything I can paint new (non stainless) car exhaust components with to inhibit corrosion and this make them last longer?

TIA!

Al

[tabbypurr]

There is. Jay Leno did a couple of youtube vids on the Doble E series, and in at least one he demonstrates a suitable coating. Don't expect it to be cheap.

I don't know if zinc dip might survive on the far end section, I suspect not.

NT

[alan_m]

Don't exhausts rust from the inside?

[tabbypurr]

yup, and the outside

NT

[Cursitor Doom]

Indeed. So you could maybe use high temperature paint to protect the outside, but it will still rot from the combustion products in the exhaust gases (no small amount of water).

[Dave Plowman (News)]

I doubt it. An exhaust usually fails where 'water' collects on the inside.

Cars that do lots of long journeys tend to have a longer lived exhaust than ones little used - which would suggest the wrong way round if it rusted from the outside.

If you intent keeping a car for any time, a SS one makes sense. The one on my SD1 Rover is over 15 years old, and never needed repair. The previous MS one seemed to need a new bit every other year.

[Huge]

Yes. If you want a system that lasts, get a stainless steel one.

[Brian Gaff]

Well, whatever youpaint it with will pong a lot. I think if it was that simple they would come with it already applied. I wonder how much anodising would cost, but of course you cannot do the Cat with that!

Brian

[Brian Gaff]

Well, a lot of what comes out of exhausts is wet, but whether they are unprotected inside I do not know. Not something I've ever looked at.

Brian

[Tim Lamb]

Sperex for the very short period when I pretended to be a boy racer:-) AFAIR OK up to dull red heat?

[0345.86.86.888]

Mate had an Escort RS Turbo and his expensive stainless pive cracked within a few years. Our POOGeot 206GTI also cracked the main pipe after 3 or 4 years which wasn't covered under warranty. So no, they don't rust but for the price there's still the risk of other failings.

[Lee]

What seems to happen is they use pipe which has had aluminised paint applied and then do the welding of various brackets and such which defeats the object. Most of the failed exhausts I saw, failed on the brackets or welds...

[Johnny B Good]

Ordinary steel ones do. Decades ago, I used to pour a pint or so of oil into new silencer/exhaust pipes prior to fitting it/them to my motor bikes in order to protect my 'investment' from the off (before any moisture had a chance to start the rotting process).

It made the bike look like a 2 stroke machine running on a 10:1 fuel/oil mix for the first mile or so before it finally cleared. It was worth the temporary smoke screen effect though since I never had any silencers fail from internal rust after that.

I figured that where the oil coating was going to be completely burnt away would remain dry anyway due to the high temperature, where it was cooler, it was going to bake a hard varnish onto the parts that might suffer short term moisture and towards the back end of the silencer where it stayed cool enough to remain wet, the oil film would provide the required protection against rusting.

[Cursitor Doom]

On Sun, 13 Sep 2015 12:24:17 +0000, Johnny B Good wrote: [...]

An intriguing theory, Johnny. Thanks for sharing. :-)

[AL_n]

Lee wrote in news:GidJx.364814$UI6.74835 @fx45.am4:

Thanks to all for the input..

Al

[Kevin]

Drill a small (say 1/8") hole at the lowest point of silencers, and the condensate will drain out even if the exhaust doesn't later get hot enough to clear it.

[Dave Plowman (News)]

And because SS doesn't rust, it's often made out of thinner gauge than an MS system. Or maybe because it's more difficult to bend. Why they're often noisier too.

[Dave Plowman (News)]

That might help if the car is always parked on the level. But I'm not convinced it does.

[Tim Lamb]

In message , "Dave Plowman (News)" writes

Might interest the MOT man:-(

[Chris French]

In message , "Dave Plowman (News)" writes

My older cars (mk3 cortina,Marina) seemed to always be needing new bits of exhaust, my wifes old (94) Punto seemed to need new bits fairly often.

But I don't ever remember having to replace anything on the Mondeo (2000 reg, we got it in 2004 - kept it for about 10 years) I don't think my wifes Yaris has anything yet since we had it either, though not sure (11 years old, we've had it for about 6-7).

Are more modern exhausts much longer lasting?