Neo Rb25 Blowing Lots Of Smoke

[theDETlife]

Gidday

A few days ago I got my rb25det neo all legal and road worthy. That night drove it very spiritedly with what i assume was quite a large boost leak. The turbo sound was loud enough you could hear it while on boost but not off boost. It sounded like a high pitched jet engine and was noticeable from inside the car with the window up and down. I haven't done a boost leak test but I will get onto that.

The next day driving the car across town i noticed when the car gets upto temp, every time you drive without stoping for a while, then start to slow down and go thought the gears, each gear shift a large puff of white/grey smoke would billow out of the exhaust, and when coming to a stop/stopped completely a very large could of smoke would come billowing out of the exhaust!

My thoughts were in this order. Loud turbo noise = boost leak -> excessive turbine speed to achieve 12 psi = turbo wheel reaching unsafe rpm's = wrecked turbo.
After some googling i'm leaning toward the fact that the turbo seals are leaking oil causing oil to burn in the exhaust. I have checked there is no sign of oil in my water or water in my oil.
Is there anyway of knowing what has actually happened or what is happening to my engine/turbo? Is it time for a new turbo? or has my head gasket blown?

The car runs very smooth on idle and drive perfectly fine, it can still boost but i assume this passed more oil through the turbo burning more oil (if that is actually whats happening).

Any help is appreciated thanks!

[AngryRB]

white/grey smoke I believe points toward oil/coolant being burnt after the engine?? so would point toward worn turbo seals, then noise maybe from broken/leaking gaskets bolts or shaft play.

If your guage takes pressure readings from the intake manifold and its 12psi, then it could be 14psi at the turbo which would probably kill a stock turbo if its old which it is.

Edited February 17, 2015 by AngryRB

[KiwiRS4T]

Done a compression test?

[theDETlife]

Cheers Mark, i believe your right about the seals, but I am fairly certain the car isn't using any water, the coolant is still very green.

No I have not done a compression test but I will get onto that. The car doesn't feel down on power at all but the smoke is very unnerving as you could imagine.

[whatsisname]

Turbocharger seals don't fail as such, worn or damaged turbocharger bearings fail and that will allow oil to leak through the seals.

Many years ago my 33 RB25DET had a piston ringland let go, no loss of power, no loss of boost, no coolant/oil mix issues, no abnormal noises, no signs of anything untowards in the catch can... white oil smoke out the exhaust was the only indicator.

[KiwiRS4T]

^^^happened to me too - blew a piston on my RB25DET - broken ringlands - still went well but used to blow the dipstick out!

[mr skidz]

pull off a breather hose from the rocker cover and if its chugs like a steam train its ya bottom end unfortunately.

[AngryRB]

My RB25 has a suspected ring land failure, has 90psi in on cylinder 5 ( always seem to be the cylinders at near the firewall ) but I never had any smoke,

certainly chugged like a train though,

[tridentt150v]

Cheers Mark, i believe your right about the seals, but I am fairly certain the car isn't using any water, the coolant is still very green.

Coolant will not be contaminated if the seals in the turbo are gone. But you will use/burn coolant and a little bit goes a long way. So what you see could be from a very small amount.

[theDETlife]

It only blows smoke when slowing down eg, down sifting with no throttle a puff comes out then when stopped it comes out in a big plume.
Turbo has about 1mm of in/out shaft play so i assume thats f**ked and about .3mm of up/down play. If it were blowing oil past the seals there would be signs of burnt oil in the down and exhaust housing of the turbo? idk what im looking at so heres a few pics of them, if someone can tell me if these are normal looking or not.
There is some signs of oil in the outlet pipes of the turbo, only small amounts coating the outside of the pipes. I was thrashing it the whole day before running 12psi with a possible boost leak so this is why i'm assuming its the turbo but i'm not sure.

[AngryRB]

Its a tough one, doesn't look stuffed to me, id try the comp test and also look at the plugs, and also the train chug as mentioned, might give some answers

You can get smoke like that under vacumn when the valve guides are rooted, first start up in morning would probably see white smoke out the tail pipe, and again when idling for long time then reviing it.. could check that too.

Edited February 20, 2015 by AngryRB

[theDETlife]

Smoke now come out in a small could on start up. (still cold) Then continues to smoke a small amount constantly.

[whatsisname]

I suggest you get it compression and leak-down tested.

[theDETlife]

bought another turbo from a R33 gtst, slapped it on and no more smoke!
After taking it for another drive down to the petrol station and back to get some gas i took the dump off and everything was coated with burnt oil! waste gate was black, 02 sensor was black and so was the dump!
Must of been the seals.