Oil in the exhaust after turbo replacement
Discussion
So, I have an old turbo diesel (no DPF, Cat or any of that crap). A while back the turbo went but not particularly catastrophically. The bearing failed and I pretty much turned it off as soon as I saw it make a cloud of oil smoke and had it recovered. Drove not more than 1/2 mile/5 mins like it.
This was the exhaust side when it had failed - I'm guessing a good 200ml of oil might have come through

Replaced everything, including a used turbo with no play in it, put it back together. Exhaust is clean and transparent when stationary, including when revved right up and left for 45 mins etc.
As soon as you drive it for a couple of minutes it starts to smoke until it's like there's a bonfire coming out of the back of it, like so:

Leave it stationary and it clears up again and doesn't smoke.
I haven't driven it much at all, as it gets a bit embarrassing so I tend to stop and turn around again.
Oil has been changed, and there's nothing in the intercooler or pipework otherwise, with the compressor side pretty clean and innocuous. No play in the shaft either.
Took the downpipe off today and checked the turbine/exhaust side, and that's also dry with no particular signs of oil presence.


The exhaust itself is a "sleeping dog", in that it looks like a complete pig to remove; not least because it's completely sealed and yet quite crusty, so any attempts to interfere with it or remove it are likely to not end well.
Is it likely to just be oil sitting in the exhaust? My assumption is that driving it is going to heat up the exhaust to a sort of 'flash point' where it's just hot enough to start burning the oil, but not when it's stationary. It makes clouds out the back as per the photo above when it starts smoking, and I simple don't have the bottle to drive it around like that in busy traffic in the daytime, so I've certainly not drive it loads. My caution before today was that it might still be symptomatic, but I'm now no longer sure that it is.
Anyone been through this before? I can't particularly see what else it's likely to be, and know that it doesn't take much oil to make lots of smoke; i just don't know how much it needs to be driven to burn it all away, or why it's not particularly an issue unless driven?
This was the exhaust side when it had failed - I'm guessing a good 200ml of oil might have come through
Replaced everything, including a used turbo with no play in it, put it back together. Exhaust is clean and transparent when stationary, including when revved right up and left for 45 mins etc.
As soon as you drive it for a couple of minutes it starts to smoke until it's like there's a bonfire coming out of the back of it, like so:
Leave it stationary and it clears up again and doesn't smoke.
I haven't driven it much at all, as it gets a bit embarrassing so I tend to stop and turn around again.
Oil has been changed, and there's nothing in the intercooler or pipework otherwise, with the compressor side pretty clean and innocuous. No play in the shaft either.
Took the downpipe off today and checked the turbine/exhaust side, and that's also dry with no particular signs of oil presence.
The exhaust itself is a "sleeping dog", in that it looks like a complete pig to remove; not least because it's completely sealed and yet quite crusty, so any attempts to interfere with it or remove it are likely to not end well.
Is it likely to just be oil sitting in the exhaust? My assumption is that driving it is going to heat up the exhaust to a sort of 'flash point' where it's just hot enough to start burning the oil, but not when it's stationary. It makes clouds out the back as per the photo above when it starts smoking, and I simple don't have the bottle to drive it around like that in busy traffic in the daytime, so I've certainly not drive it loads. My caution before today was that it might still be symptomatic, but I'm now no longer sure that it is.
Anyone been through this before? I can't particularly see what else it's likely to be, and know that it doesn't take much oil to make lots of smoke; i just don't know how much it needs to be driven to burn it all away, or why it's not particularly an issue unless driven?
Edited by cj2013 on Sunday 3rd April 13:14
Edited by cj2013 on Sunday 3rd April 13:14
You know the exhaust is full of oil and if you haven't cleaned that out it's going to burn off. Even a small amount of oil produces a huge amount of smoke. That accounts for at least part of the problem.
It's possible the new turbo is also leaking oil but you mention the header is clean and dry so there's no evidence of that.
If it was me, I'd try to get it somewhere where it could burn off the oil without inconveniencing other people, using a sequence of short moves if necessary to avoid it getting hot.
It's possible the new turbo is also leaking oil but you mention the header is clean and dry so there's no evidence of that.
If it was me, I'd try to get it somewhere where it could burn off the oil without inconveniencing other people, using a sequence of short moves if necessary to avoid it getting hot.
GreenV8S said:
You know the exhaust is full of oil and if you haven't cleaned that out it's going to burn off. Even a small amount of oil produces a huge amount of smoke. That accounts for at least part of the problem.
It's possible the new turbo is also leaking oil but you mention the header is clean and dry so there's no evidence of that.
If it was me, I'd try to get it somewhere where it could burn off the oil without inconveniencing other people, using a sequence of short moves if necessary to avoid it getting hot.
To be fair, I wouldn't say I suspect it's full of oil; I don't really know for sure. It's kind of an occam's razor thing.It's possible the new turbo is also leaking oil but you mention the header is clean and dry so there's no evidence of that.
If it was me, I'd try to get it somewhere where it could burn off the oil without inconveniencing other people, using a sequence of short moves if necessary to avoid it getting hot.
I think I might have to try and take it for a country lane drive when it's late and dark
Edited by cj2013 on Sunday 3rd April 16:11
mickyh7 said:
PH at its Environmentally Best!

Clarify for me how burning off some 100ml of oil - at the most - in the exhaust is somehow environmentally worse than new engines that believe it's "normal" to consume 10 times that amount per 1000 miles?
https://www.pistonheads.com/gassing/topic.asp?h=0&...
cj2013 said:
Clarify for me how burning off some 100ml of oil - at the most - in the exhaust is somehow environmentally worse than new engines that believe it's "normal" to consume 10 times that amount per 1000 miles?
https://www.pistonheads.com/gassing/topic.asp?h=0&...
You have no idea how much oil is in there.https://www.pistonheads.com/gassing/topic.asp?h=0&...
You've already said you think it's full of oil.
If your feeling clever, go and burn it off outside a Police station, and argue it with them?
You have no control over a new engines appetite.
But you have a conscience over this one.
Your choice.
mickyh7 said:
You have no idea how much oil is in there.
You've already said you think it's full of oil.
No, I haven't actually. In a thread of so few posts it seems like you've made a hill to die on without even attempting to be helpful, or even read the posts.You've already said you think it's full of oil.
As physics remains intact here, I certainly know that the amount of oil is the absolute maximum between the capacity of the engine and what was drained after I replaced the turbo, and as stated it is at most approx 200ml minus what was in the turbo as pictured.
mickyh7 said:
If your feeling clever, go and burn it off outside a Police station, and argue it with them?
You have no control over a new engines appetite.
But you have a conscience over this one.
Your choice.
If you had some reading comprehension, or at least paid attention, you'd realise that I'd already gone to efforts to avoid running it in a BUA where the emissions would be a nuisance, so your comparison is basically not really an outlier to the level of thought applied to the rest of your argument.You have no control over a new engines appetite.
But you have a conscience over this one.
Your choice.
When I'm not using this car, I drive one with zero emissions, so people do very much have control over the oil consumption of a new 'engine'. You also have the control over what vehicle you choose to drive.
It's such a bizarre line of thought - am I supposed to believe that less emissions will be burnt throwing either the exhaust or the entire car into landfill and/or the production of a new exhaust by virtue of it being cleaner?
mickyh7 said:
To be fair, I would say I suspect it's full of oil; I don't really know for sure. It's kind of an occam's razor thing.
I think I might have to try and take it for a country lane drive when it's late and dark
That's clearly a typo, or else the reply makes no sense.I think I might have to try and take it for a country lane drive when it's late and dark
Driving a car down a country lane is not "outside a police station" or in a built up area. Are you oblivious to the emissions of farmers vehicles?
mickyh7 said:
Your coming across as a complete Dick.
Read your own post.
Ironic..Read your own post.
mickyh7 said:
And of course your zero emissions vehicle made no emissions on production 
That's not what "zero emissions" means.
Crikey, you're a sort.
VanDiesel99 said:
I'd be inclined to take it out in the wee small hours, see if it 'Burns Off'.
Take sufficient tooling that you can block off the Air Feed to the engine, just so's you know that you can cope with a 'Runaway' should it misbehave
You only need to stall a runaway Diesel to stop the engine.Take sufficient tooling that you can block off the Air Feed to the engine, just so's you know that you can cope with a 'Runaway' should it misbehave
I'd pay good money to watch this one runaway though.
Edited by mickyh7 on Wednesday 6th April 12:11
Yes, I have history with oil in an exhaust burning off.
Had a Mazda 323 with a worn out engine, the thing drank more oil than petrol at times, the bores were shot.
I was out of the country, my dad had the engine re-built, and drove V gently for 500 or so miles.
I come back, and take the car for a long drive, very much aware of the new engine under the hood.
After a while the exhaust started to warm up, and very quickly I had a smoke screen following me.
I panicked lots.
Checked things over quickly, worked out it was just the oil in the exhaust, and went on my merry way. The smoke screen did not last long at all.
If I were you I would go for a gentle longer drive, slowly get everything up to full temp. Yes, this will create a small smoke screen, but I do not think it will last long. Full throttle will make it much bigger.
Had a Mazda 323 with a worn out engine, the thing drank more oil than petrol at times, the bores were shot.
I was out of the country, my dad had the engine re-built, and drove V gently for 500 or so miles.
I come back, and take the car for a long drive, very much aware of the new engine under the hood.
After a while the exhaust started to warm up, and very quickly I had a smoke screen following me.
I panicked lots.
Checked things over quickly, worked out it was just the oil in the exhaust, and went on my merry way. The smoke screen did not last long at all.
If I were you I would go for a gentle longer drive, slowly get everything up to full temp. Yes, this will create a small smoke screen, but I do not think it will last long. Full throttle will make it much bigger.
mickyh7 said:
CarCrazyDad said:
Are things OK in your life ?
You seem very angry.
My life is incredible thanks. You seem very angry.
Everything about it is good.
Can't understand why your concerned about a stranger though.
Jog on Son.
Take a step back , no need for it really is there

mickyh7 said:
You've been made to look stupid on the Cycling crash thread, so jumped on here to try your luck?
Get a life!
???Get a life!
I'm not being angry online. I've not been made to look stupid on the cycling thread.
I'm just saying no need for your attitude on this post... You've been militant from the start.
Gassing Station | Home Mechanics | Top of Page | What's New | My Stuff


