View Full Version : Blue exhaust smoke, any ideas?
risky business
19-06-2001, 00:35
When my S13 is revved, as the revs drop back to idle and particularly during the first few seconds of returning to idle, the exhaust emits blue oily smelling smoke. However,it doesn't emit smoke during the acceleration phase.
This problem appeared all of a sudden towards the end of a track day. The turbo sounds fine and the cars' performance is still the same. Does anyone have any idea what the problem is? .
Thank's.
Hi!
It would appear your turbos knackered mate.
Clasic scenario is where you come flying up to a roundabout and sit in traffic - only for a plume of bluish smoke to waft past the car!
It's basically your turbo oil seals - the centre ones I believe.
During accelaeration the turbo core is in effect pulling itself towards the front of the car in the housing (like a jet engine in a plane). at this point, the oil seals are compressed. As you come off the gas, the pressure is relieved from these seals and oil drips into the exhaust airflow - giving the smoke out the back. You're not really doing any harm at the moment - its just a bit embarassing. The thing I found when I had a smoker on my first S13 is it would only smoke as I pulled up to some nice girl standing outside the shop or something - (bugger).
It may not seem to affect the performance, but over a period of time, the bearings would go and thats when you start to get "scraping" noises, as the cold wheel hits the housing.
Hope this helps
Matt
Hey nice explaining Matt, always wondered why smoke comes out when turbo's gone, now i know. Lets see if you can solve this one,
I've posted this before on the old forum but didn't get any answers... just laughing, my idling's a bit funny, it used to stay put but now it searches and shakes the car, even when i hold something like 2000 revs the car still shakes, does anyone know whats wrong
cheers
Matt_S Wrote:
It may not seem to affect the performance, but over a period of time, the bearings would go and thats when you start to get "scraping" noises, as the cold wheel hits the housing.
Err.. scraping noise? I currently have a scraping noise but I think it's a bit different luckily (or not? who knows). My noise is speed-dependent (seems to drop a lot after 40mph, any gear), and turning right basically stops it altogether. That wouldn't be the wheel hitting the housing would it ?
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Graphite Grey S13
HKS Hiper Muffler / KYB Shocks / Avo Springs - Running so, so sweetly!
I was surprised to hear how much oil actually makes that much smoke.
Apparently, when sat at the lights and the damn thing starts smoking, it only takes literally 1 or 2 drips of oilto get through the seal and all that smoke is produced. OK the worse the seals get, the more oil will get through, but mine was a proper smoke screen at the lights and it was all caused by 1 or 2 drops of oil.
Stu
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Stu
DIY T3, FMIC, but need more power!!
Yes, its a pain isnt it, I have had the smoke screen modification done to my turbo too. Its a horrible feeling being at lights, just waiting for the inevitable..
risky business
19-06-2001, 10:18
Many thank's for the info.
Does anyone know of a reasonable garage in the South East who could repair/replace my turbo?
olly200sx
19-06-2001, 11:36
I wouldn't necessarily call it the turbo, the valve stem oil seals could also have worn, and they are prone to it too on these motors. Once the engine is warm and you take it for a thrash then pull up it emits smoke for a while, don't rule them out and think its always the turb' !
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S13 - Lots of Mods
Kristian
19-06-2001, 12:46
I agree entirely with olly and dont think its necessarily the turbo. To check the turbo: remove the inlet pipe (from the air filter). You will then see the turbo shaft. PULL this IN and OUT. If there is any movement more than the smallest fraction then the turbo is on its way out. NOTE: this is called end float and is what you are looking for. You CAN move the shaft up and down as it is on bushes and there is some play. However, it is the in and out movement you are looking for. Any of this and the turbo needs replacing or overhauling. My car is currently doing it and it too happened aftera track day. I believe it is the valve guides/oil seals. These can be done without removing the cylinder head and i would advise doing this before your turbo especially if there is no end float. My turbo is fine, Its a hybrid thats done 20,000 miles so it should be!!! I still get the odd cloud of blue smoke but it is very sporadic. Also when my original turbo went it was very obvious. You get great clouds of smoke and its more white than blue. Hope this helps a little.
Originally posted by olly200sx:
I wouldn't necessarily call it the turbo, the valve stem oil seals could also have worn, and they are prone to it too on these motors. Once the engine is warm and you take it for a thrash then pull up it emits smoke for a while, don't rule them out and think its always the turb' !
Kristian
19-06-2001, 12:49
When i say "from the air filter" i mean the pipe from the air filter that goes to the turbo. You need to rmove this inlet pipe from the turbo not at the air filter end. Hope this clears any problems.
Originally posted by Kristian:
I agree entirely with olly and dont think its necessarily the turbo. To check the turbo: remove the inlet pipe (from the air filter). You will then see the turbo shaft. PULL this IN and OUT. If there is any movement more than the smallest fraction then the turbo is on its way out. NOTE: this is called end float and is what you are looking for. You CAN move the shaft up and down as it is on bushes and there is some play. However, it is the in and out movement you are looking for. Any of this and the turbo needs replacing or overhauling. My car is currently doing it and it too happened aftera track day. I believe it is the valve guides/oil seals. These can be done without removing the cylinder head and i would advise doing this before your turbo especially if there is no end float. My turbo is fine, Its a hybrid thats done 20,000 miles so it should be!!! I still get the odd cloud of blue smoke but it is very sporadic. Also when my original turbo went it was very obvious. You get great clouds of smoke and its more white than blue. Hope this helps a little.
same problem here
checked the turbo today seemded fine then i took the hose from the rocker covers of the hose to the turbo stuck my finger in it and the smoke was gone?????
gonna figger this out tomorrow
(sorry for the bad english)
Kristian
20-06-2001, 11:59
When you stuck your finger in did anything come out??? was there any blockage???going to check mine tonight.
Originally posted by tubbie:
same problem here
checked the turbo today seemded fine then i took the hose from the rocker covers of the hose to the turbo stuck my finger in it and the smoke was gone?????
gonna figger this out tomorrow
(sorry for the bad english)
risky business
20-06-2001, 14:23
Many thank's, will give it a go.
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Black S13
Uprated Actuator
ND Stage 1 Eprom
Janspeed D-Cat Pipe
olly200sx
20-06-2001, 15:58
When you say "stuck your dinger up it" I presume you mean you stopped the crankcase breather going back into the intake before the turbo !, if that is the case then it means that breather is pushing oil into the intake before the turbo, causing the smoke. A little is normal, but it shouldn't cause smoking as it usually all gets burnt, maybe your other breather pipes are blocked or the pcv valve !!!
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S13 - Lots of Mods
i had two broken valves and bad piston rings so i had that fixed two months ago.
but still it smoked like hell only after letting it rev down.
he really quits smoking if i block the breather pipe.
so i cleaned all the pipes today and one of the rocker covers, they were really dirty but not blocked.
after that he still smoked.
tommorow i gonna check the pcv valve and the i.a.a. unit maybe there's the problem.
i hope it is.
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black 91
green airfilter special made exhaust
oh dear... this smokiness is still a problem for me, it seemed the original t25 was on its way out and the gaskets were totally dissolved so i decided to totally replace it all with a T28 hybrid from norris, the turbo was great and any smoking ills i presumed would be cured also.....not so, about a week after getting the brand new turbo on and having worn it in gently, blue smoke would eek its way out the exhaust from time to time, the worst after a blat and coming to a standstill in traffic when it was chucking it out......very unhappy....
so's i ring norris and he is cool saying he has seen the problem before, saying it was the oil breathing and it needs sorting with a big clean under the rocker covers and tubes etc. i will be taking my car back in a month to see if this will cure, i can't imagine a brand new t28 is knackered after 1,500 miles, having said that, the turbo is buzzing on pick up and boost for the first 10 minutes of driving the car, doesn't sound nice.....ANY SUGGESTIONS?? please put my mind at rest....
boo hoo
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DRIFTING?? I don't believe i was, officer....
Matt, the buzzing / whizzing when cold may well be that the turbo has worked a bit loose. Check the Exhaust side, the likelyhood is one or more of the 5 bolts has worked loose (definately a common prob i think) It goes away after 10 mins coz it seals itself a bit when it gets hotter. This *may* explain a bit of crumby performance. Especialy if its the turbo inlet from the exhaust manifold that has come loose, meaning the turbo isnt being spun up as early and as fast as it should.
* I got the smoke too btw, and my turbo seems to be in good condition. If anyone has success with this breather thing, Id be interested to hear about it. Especailly since someone has had new valves and piston rings and it still does it!
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Dan
Red S13
Actuator/chip/filter/Mong00se
http://animatedgif.net/animals/otheranimals/ape_e0.gif
[This message has been edited by Chimp (edited 21-06-2001).]
Has anyone actually tried doing the valve stem oil seals to cure this smoke prob? Its hard to believe that we all have knackered turbo seals or blocked breathers.
olly200sx
21-06-2001, 13:19
As I said earlier I did have this problem on my old uk spec engine and yes I did the valve stem seals and yes it did cure it 100%, I'm not saying it will for everyone as different cars do it at different times and for different reasons, but they are a common problem on these motors !!!
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S13 - Lots of Mods
well after this morning i figure it has to be the one rockercover i did'nt clean it must be blocked gonna clean it tommorow
and if that's not the cure i'll just buy an gasmask
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black 91
green airfilter special made exhaust
Cheers olly, soz i didnt see it posted before. I've been suss about it being the turbo. I'll be so effin pleased if stem seals sort it. Then all I have to worry about is the crank http://300zx.co.uk/200sx/ubb/tongue.gif. Did you do them yourself? If so is there a dodgy special Nissan tool for them? or is it straight forward enough.
Dan
risky business
21-06-2001, 15:31
Examined the end float of my turbo shaft. Found that I could move it in and out by about .5 to 1mm.
Is it a very involved job to inspect the valve oil seals?
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Black S13
Uprated Actuator
ND Stage 1 Eprom
Janspeed D-Cat Pipe
If you go to the hassle of checking them, you would be 90% the way there to changing them i think. Not sure how expensive seals are though, cant be too expensive.
oh oh oh mr.chimp, u may have hit the nail on the head as it seems.....
the turbo does spin up later for some reason, around 4000rpm and above, can't see much on the turbo with regard to bolts as yet and i didn't want to follow ur hand burning tactics just yet http://300zx.co.uk/200sx/ubb/smile.gif
spoke to norris as i had a careful listen to the turbo and decided it sounded like a rattlesnake about to bite my ass, so's i tell him this and he goes, "A WHAT?? A RATTLESNAKE?? WHAT THE... I HAVE NO IDEA AT ALL...WHAT ARE U DOING??".... hehe heh, expected really as i rang up the day after i had my turbo fitted there to congratulate norris but instead i used my "humour" to convince norris that i had ragged the car at 145mph for about 10 mins just after having the work done.... i then ranted that i wanted my money back and i wasn't happy, it didn't turn out that funny for norris and it took a whole lot of explaining to convince him other wise, i believe i am now his nemesis, and maybe he's trying to finish me off in some way.....arf, or NOT and i need to be professional with him like i should be....DAMMIT!!!
MATT
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DRIFTING?? I don't believe i was, officer....
well i hope you suss it out, specially since its a new turbo. 2 hours ago i was happy in the thought that my valve stem seals might make the blue smoke away. However I just got back from the most embarrasing drive of my life, its got beyond a joke now! Raced a cav GSI home down the M53, both pulled off at the same junction and I briefly had a grin coz i whooped him, about 2 seconds after i pulled up, my car was engulfed in blue smoke, and everyone elses, and the road signs, houses, women and children.. etc..
Not a happy bunny. Surely my turbo is dead, I shall find out in due course i guess. http://300zx.co.uk/200sx/ubb/frown.gif
olly200sx
22-06-2001, 10:31
Now that would seem a lot more like the old turb' has gone, the valve stem seals don't usually below a lot out, but enough to be noticeable !!! They cost about 80p each !!!
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S13 - Lots of Mods
Kristian
22-06-2001, 10:36
The hissing noise is defintely the turbo gaskets. Mine did it shortly afte having fitted the hybrid and lasted for several months. Once heated up it expands and stops the noise as the gap is sealed. You need to check these. New gaskets come to £65 for the whole lot. Performance is also useless while this gasket is leaking as your loosing the benefit of the turbo. I've now renewed mine after they totally went and there fine. just make sure its all done up damn tight!! I too nead to renew my valve guides/oil seals as i too get some smoke. Not masses though!.chimp, it does sound like your turbo given the amount of smoke you speak of.
Originally posted by Chimp:
well i hope you suss it out, specially since its a new turbo. 2 hours ago i was happy in the thought that my valve stem seals might make the blue smoke away. However I just got back from the most embarrasing drive of my life, its got beyond a joke now! Raced a cav GSI home down the M53, both pulled off at the same junction and I briefly had a grin coz i whooped him, about 2 seconds after i pulled up, my car was engulfed in blue smoke, and everyone elses, and the road signs, houses, women and children.. etc..
Not a happy bunny. Surely my turbo is dead, I shall find out in due course i guess. http://300zx.co.uk/200sx/ubb/frown.gif
well i cleaned both rocker covers one was very dirty.
the smoke is less but still there however if i put my finger in the pipe from the exhaust rocker cover to the turbo air inlet the smoke is gone if i rev it to 2500-3000 rpm
and then let go idle again
if i drive he begins smoking at 1900rpm untill about 2300rpm
so most likely the valve oil stems are blown due to bad breathing of the rocker covers
cos if under 1900 rpm the pcv valve creates a vacuum and above 2300rpm the engine sucks the air out.
i finally convinced the nissan dealer who fixed my cilinderhead and replaced my piston rings that it is not the turbo so know he will fix it next week
the car feels much better after the breather cleaning bytheway
wishing we had something like norris or se in holland
happy weekend
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black 91
green airfilter special made exhaust
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