Light blue Smoke

[caterpillar]

if you have rebuid the turbo resent....take of the tube from the filter at the turbo,then have the fingers on the inntaketurbo(NOT AT THE ENGINE RUNNING):if you can take the axel and tubin IN AND OUT,only a litle bit,the trust bearing in turbo is gone.up and down it shud be,because the oil have the passage in the bearing.

[charlie]

Thanks for all the feedback guys;
The following is things to do-
1) check cold side of turbo (when car is cold and clean my MAF
at the same time).
2) remove IC and check for oil ( might do the M/H
conversion at the same time)
3) replace rockercover gasket( torque setting 10nm???)

FOOD FOR THOUGHT
Surely if the stem seals are leaking, shouldn't the spark plug
in that cylinder be covered in oil/soot coz after installing
new plugs 600 miles ago they seem to be covered in soot/carbon.
Is this normal???

[ericd]

Thanks for all the feedback guys;
The following is things to do-
1) check cold side of turbo (when car is cold and clean my MAF
at the same time).
2) remove IC and check for oil ( might do the M/H
conversion at the same time)
3) replace rockercover gasket( torque setting 10nm???)

FOOD FOR THOUGHT
Surely if the stem seals are leaking, shouldn't the spark plug
in that cylinder be covered in oil/soot coz after installing
new plugs 600 miles ago they seem to be covered in soot/carbon.
Is this normal???

When the turbo let go on mine (oil seal), same symptoms as you describe, I started from the exhaust & worked forwards (too many years walking around inside computers makes you're logical thought processes different...),

Anyway, lambda probe was the first thing I got to & it was covered in oil !, followed oil trail through pipe/s to hot-side of turbo.

Worth the few mins to check the lambda in my case...

Hope you find the cause soon.

[Dr H]

When mine went it only ever smoked at tickover, never on gear changes or at revs. It used to give out puffs of smoke at completley random intervals.

When AET rebuilt it they said there was a minute ammount of wear that was only detectable by measuring it with a micrometer (or vernier or whatever they used) the reason it was smoking was that I had removed the CATs and the drop in back pressure had shown up the very small ammount of wear.

Only had 55,000 miles on it at the time - they said the damage looked like pure bad luck as there was nothing obviously wrong and no signs of oil starvation or overheating.

[audiman]

AET's work is very good. I would suspect that its NOT the turbo, more likely to be the VS oil seals. If they are fitted badly and tapped onto the guide just a little too hard, they go oval shaped and dont seal properly. Either that or they never bothered to fit the new ones as supplied. Dont know who did the work, but i trust it was someone decent with a good reputation?

[charlie]

Hi,
It was someone on this forum. No prices for Guessing
But their still is oil leaking from turbo to IC. this should not happen
on a turbo thats only 4 months old and less than 500 miles
Will give Ian at AET a ring but its the process of stripping the turbo
Down again
I know its only very little smoke occasionally when not driven
for a few days, and the car is very fast and punchy, but...but...

[audiman]

Turbo's very rarely fail on the cold side. More likely heavy breathing engine or VS oil seals.

I think I know who you mean now Nuff said

[charlie]

Cheers Audiman,
Can you elaborate on heavy breathing. would type of engine oil
aggitate this???

[audiman]

worn piston rings or bores. A thin engine oil would make this worse. IMHO i think its VS oil seals. Mine used to do the same until I changed them. After being stood still for 3 days or so, it would smoke on start up. After changing them correctly it has never done it since.

[charlie]

Im 90% sure its the turbo. I will relay my thesis later. require a bit more
diagnostics

[Graham]

I too have a similar problem, when i start the car up first thing i get a single puff of smoke, i changed the stem seals, when i fit them i just gently pushed them on by hand using a piece of turned bar which exactly fits on to the metal ring of the seal without touching the rubber. But i am fairly certain my turbo is not in A1 condition and my PCV system is still a bit suspect.
Graham

[charlie]

update

When the car is idleing for some time then you accelerate or bleep, the
throttle, thats the only time it smokes. . by now all the oil in the system should have burnt off. I read a thread earlier on and have suspecions
about the turbo. Well its coming off and going back to AET .

Would a 3" downpipe and cat bypass pipes have any effect. :mischeif:
Feedback always appreciated.

[Greenm3]

I have the same mtm tuning and have no cats and same exhaust...mine smokes in the same way....just done the ic M/H conversion....much better now.....though still have a reasonable amount of oil from turbo to ic still.....i reckon a recon turbo needed soon....

[charlie]

Update

Done my IC mod yesterday evening, took about 2 hours as i was doing it
alone and found oil deposits in bottom of IC. The only way that can get
in there is is from the turbo.
Cleaned the IC internally and externally. From memory it seems to be
alot harder than 3B/ABY IC.
At the same time cleaned the MAF and installed Airfilter directly onto
MAF but no heatshield.
Good news is that it now peaks at 25 psi and drops to 23/24 psi all the
way to 7000 rpm. Boy is it quick and nice induction noise and you can
really hear Forge piston DV earning its money
Is their really a downside to connecting filter straight onto MAF???

[SteveH]

Charlie, If you have the original PCV system on the car, the oil deposits in the IC could be from that. In fact, it's more likely they are from the crankcase fumes than the turbo. I've experienced a few turbos that have leaked oil at the hotside, however, non that have leaked via the coldside.