Technical Exhaust Backbox Corrosion Issue
- Thread starter Mark Elvin
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Technical Exhaust Backbox Corrosion Issue
Shade under 7k.
Odd thing is the rust on the silencer doesn't look particularly structural.
Pretty peeved that a 7 month car is technically an MOT failure (and I suppose technically un roadworthy too
). I quite fancy the idea of a stainless exhaust, but with such an uncertainty hanging over the future of the car I'm not sure it's worth it.
Others; Please check you back boxes and let's see how widespread the problems are.
Pretty peeved that a 7 month car is technically an MOT failure (and I suppose technically un roadworthy too
). I quite fancy the idea of a stainless exhaust, but with such an uncertainty hanging over the future of the car I'm not sure it's worth it.Others; Please check you back boxes and let's see how widespread the problems are.
In general I agree; OEM parts are usually far superior to the aftermarket products used by the likes of Kwik Fit.
Not on this car, though. I've removed the backbox from an almost new 500 for these photographs.
This car has been garaged since delivery mid March, has done only a few hundred miles and has never been driven in the rain.
Corrosion is already starting around the seams, on the pipes, and on the welds attaching the pipes, hangers and trim. There is no evidence of any kind of protective treatment and without immediate attention I would be surprised if this exhaust would last more than about 18 months in our British climate.
I've left the pictures in high resolution in case anyone is interested in the detail.
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I had two silencers replaced for corrosion within the warranty period on a Daihatsu I owned once. They just dissolved.
We have had a truly awful winter though, and I bet that not many people have washed the undersides of their cars regularly to get the salt off. Also, lots of short journeys that prevent the silencer systems getting hot and evaporating moisture on the inside will just add to the problem. I have never had a whole exhaust system last more than four years, although the back box on my seven year old Doblo is still original. I think it will need replacing before this year's MOT though.
Silencer systems are like tyres, they need replacing from time to time, and the type of usage makes a huge difference. In a dry salt-free climate the things go on for years.
We have had a truly awful winter though, and I bet that not many people have washed the undersides of their cars regularly to get the salt off. Also, lots of short journeys that prevent the silencer systems getting hot and evaporating moisture on the inside will just add to the problem. I have never had a whole exhaust system last more than four years, although the back box on my seven year old Doblo is still original. I think it will need replacing before this year's MOT though.
Silencer systems are like tyres, they need replacing from time to time, and the type of usage makes a huge difference. In a dry salt-free climate the things go on for years.
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I still think an exhaust blowing at 7 months is bordering on farcical.
I agree completely, The state of your exhaust is appalling for a car so new.
Are you sure it's actually blowing, though? There's an intentional small drainage hole in the lower front of the back box (see attached photo of the one I removed this afternoon from a practically brand new car) and a small amount of exhaust gas will blow out of this hole. You will also likely find a layer of soot around this hole (I'd already cleaned mine off before taking the photo). This is completely normal and won't cause your car to fail an MOT.
However, the extent of the visible corrosion on the seams of your back box is worrying, given the age of your car, and will ultimately lead to perforation and failure.
There are also 3 holes drilled into the outer sheet of the top of the can, which appear to serve no useful purpose (though they're perhaps needed in the manufacturing process). I've posted a photo showing these, and also a closeup of one of the holes. There's another sheet of steel immediately underneath these holes, so they are effectively blind - but will allow salt spray thrown up from the rear wheel to get into the innards of the box and accelerate corrosion. I suspect this could be the cause of Mark Elvin's failure as they could easily be mistaken for spot welds in a corroded exhaust.
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I'm not sure. That hole would certainly be in the right sort of area, but the soot distribution looked like it was seeping from the seam on the bottom. I'll have another look tomorrow (if I can find my wax. Car really needs it.)
Zanes
The welded seams are on the other side of the end plate to the hole. The metal on the side with the soot is just folded over (much easier to see when the box is removed) and so is not in a place I'd expect it to fail first. Fingers crossed for you that yours is not as bad as you might have first thought.
My comments about the (lack of) quality of this exhaust still apply, though.
What I'm attempting now is some sort of preventative treatment to try to extend the life expectancy of my exhaust - remembering that it will also be corroding from the inside out.
The welded seams are on the other side of the end plate to the hole. The metal on the side with the soot is just folded over (much easier to see when the box is removed) and so is not in a place I'd expect it to fail first. Fingers crossed for you that yours is not as bad as you might have first thought.
My comments about the (lack of) quality of this exhaust still apply, though.
What I'm attempting now is some sort of preventative treatment to try to extend the life expectancy of my exhaust - remembering that it will also be corroding from the inside out.
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I don't quite see what the problem is? The spatter from welding is always going to rust, it just is. There is a hole in the bottom of the box too which allows condensation to run out the bottom, the holes at the top may help the vapour to escape through the top.
With the amount of salt that was on the roads this year it's no wonder that the exhausts are rusty. It's been the coldest winter for decades and they were spreading salt on the roads like a fatty spreads butter on their sandwich.
People on this forum don't seem to be able to see the wood for the trees. Things like exhausts, discs, drums etc etc get rusty and they're consumables which you WILL need to replace should you keep the car long enough. As long as the galvanising on the body is up to the job the body should still look fantastic in years to come as long as you wax it regularly.
I'd KILL to be in the situation where the biggest issue with the wifes car is a rusty exhaust
Seriously people, enjoy your cars and quit worrying so much about little things like this. I've spent £430 over the last few months just on parts for the darn thing so it can go in next week to get the steering, brakes and about half of the suspension bushes all sorted next week when we'll probably get a silly bill for labour too.I don't quite see what the problem is? The spatter from welding is always going to rust, it just is. There is a hole in the bottom of the box too which allows condensation to run out the bottom, the holes at the top may help the vapour to escape through the top.
With the amount of salt that was on the roads this year it's no wonder that the exhausts are rusty. It's been the coldest winter for decades and they were spreading salt on the roads like a fatty spreads butter on their sandwich.
People on this forum don't seem to be able to see the wood for the trees. Things like exhausts, discs, drums etc etc get rusty and they're consumables which you WILL need to replace should you keep the car long enough. As long as the galvanising on the body is up to the job the body should still look fantastic in years to come as long as you wax it regularly.
I'd KILL to be in the situation where the biggest issue with the wifes car is a rusty exhaust
Having to fork out £250 for car thats still in warrenty with an exhaust less than 2years old? Fair enough if its 4-5 years old but at this stage is pretty poor. It was a bad winter but to be fair they ran out of salt round here so can't even blame it on that! Part of the reason of buying a new car is to avoid these unexpected costs for a couple of years.
Are any of the exhausts really that bad though? Perhaps one or two. But Jrkitching's exhaust barely has any surface rust!!!!!!
Couldn't agree with you more. Even Kwik-Fit would seem to be offering a 3 year guarantee on their exhausts now.
As the durability of the OEM part may be suspect, those of you whose exhausts have already failed may be considering replacement with an alternative, perhaps in stainless steel. I wonder, though, if fitting a non-FIAT approved exhaust might be construed by FIAT as invalidating the engine warranty? I'm not suggesting for a moment that fitting an aftermarket exhaust might damage your car - but I have a horrid feeling that, particularly in the third year dealer warranty period, the insurers underwriting the warranty might use every trick to avoid having to pay out.
jrkitching's exhaust has been taken straight off a brand new car and shows that, even when new, the seeds of corrosion are already there. True, it's just on the surface right now, but rust will quickly develop once started - the key is to stop it from starting in the first place. I've seen 2 year old cars with less rust on their exhaust than that.
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Mines gone or very close too going. At first I thought it was the drain hole but it appears that there may be a leak. Its not as bad as Marks was but come MOT next spring I imagine it will need changing
I haven't read this as thoroughly as I should, but do I take it that they are expecting you to PAY for a new exhaust? Sure, they are wear items, but they should last longer than two years without perforation.
Meh, it's surface rust and most of the rust is on very thick parts like the pipes and it'll take effing ages for that rust to actually go all the way through.
This is 16 years of rust on a suspension arm and my mechanic still says it's absolutely fine. Disregard the circle btw, that hole is actually meant to be in the arm
Perforation on a fairly thick bit of steel like the stuff used on the pipes and exhaust endplates is not the work of a couple of years. Sure the actual casing for the box might not be particularly thick and could be improved on perhaps but it aint the end of the worldAttachments
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Well, just had another poke around mine and happily it *looks* like the soot is being blown back out of the drain hole. Shall be keeping an eye on it though.
Mine has this soot too. Has some rust on the box and on the rear pipes but will be fine for another few years yet and when it does go it'll be replaced by an SS rear box.
I'll be honest, I didn't realise backboxes had drain holes, and I've always associated any sign of soot with a leaky system. Still, if I decide to sell up later this year looks like it'll more than hold until then and if I keep it longer a system ala marks would be on the cards anyway
