2.0 Turbo, Smoking On Idle?

[Headling 0]

hi guys, had a blast in a mates 2.0 turbo pug at the weekend, just had a turbo re build and been running for about 6 months at 0.9 bar boost, goes really well btw.

 

Had a slight problem thats confusing us ( not hard!), after a good run when hot when the car is at idle grey smoke, oily smelling comes out of the exhaust, once you have got on the move again it clears itself and doesnt smoke when on boost again.

 

I thought it could be valve stem oil seals, so did the 3rd gear rolling down hill off the throttle, booted it and no smoke?

 

So is it a seal in the turbo? or any other things to look at?

 

The turbo is still under warranty so could send it back.

 

Your help is much appreciated.

[wracing 19]

wrong oil those turbos need an expensive 10/40 fully syn to not smoke, my turbo conversion smoked like a beast at idle as soon as i put proper oil all smoke gone!

[sounds of silence 2]

better getting total sealed rings put in the turbo this prevents it from happening its all to do with back pressure

 

also alot to do with the breather system on the engine

[Headling 0]

I can't see how an oil change can cure it? Something must be wrong? Seal gone somewhere ?

 

I'm open to try it but don't want to waste a load of cash on good oil for it not to fix it. I'm using semi syn 10/40 at the mo.

[Headling 0]

Thanks for the relpy SOS, love your car btw! I'll ring the turbo centre who re built it and ask them what seals they used.

 

Any tips on breather system??

[sounds of silence 2]

yes mate use a proper breather/seperator with a one way valve which works off vacuum and it ll work 100%

 

another solution is alter the exhaust system to create more back pressure not what you want for the performance from a turbo engine but will cure the smoke problem

[wracing 19]

Different oils different properties there was a topic on here not so long ago with someone doing a 2.0t conversion, smoking....oil changed....no smoke.

 

It could be a seal but for the sake of oil change..... Also think about it cold oil nice and thick, hot oil thinner pushed past seals.

 

Choose oil that performs better under higher temps and retains its viscous properties.

 

I have to agree on the breather side of things those one-way valves off the td and 2.0t petrol are the way forward, first day out in my car my engine bay was well lubricated put it that way.

[Headling 0]

Ok were going to give the oil change a go and see what happens, if not then I'll whip the turbo off and send it back to Turbo Centre for a look, I would have hoped it would not have failed in 6 months, its only a weekend toy so only done 1000 miles if that.

 

SOS, if you have any pics or links for the bits for the one way valve etc that would be great, shame your so far away id love for you to sort it all out!

[wracing 19]

this is a 1.8turbo 205 you can see the valve clearly.

 

[Headling 0]

Thanks for the pic, the valve is fitted, large round plastic thing! and a right angle which is going to atmosphere, where should this be hooked into? Will this make a difference?

[wracing 19]

this one is fitted to the turbo intake pipe so there is a negitive pressure applied to it.

[sounds of silence 2]

we found them to still be useless tbh

 

the breather we made is a proper breather say like a baileys cosworth one and the valve actually is cosworth related as well takes a vacuum feed to work the one way valve and works 100%.

[rapidmi 4]

we found them to still be useless tbh

 

the breather we made is a proper breather say like a baileys cosworth one and the valve actually is cosworth related as well takes a vacuum feed to work the one way valve and works 100%.

 

yip

[Headling 0]

I spoke to turbo centre today, they think oil return line to sump could restrict flow or it's the oil air breather? Is it ok to run it with out breather to check it out? And could I stick a little k and n filter on the pipe? Or is the one way valve route SOS talked about worth doing??

[Guest Rallyesmoker]

Thats what they always say....

 

2 things you can do. More back presure in the exhaust, or place a restrictor in the oil feed line. This makes the oil pressure up to the turbo sligtly lower, so the oil won't go by the seals in the turbo.

 

Breather options and oil can help, but mostly for short time. The problem is the t25 itself and the open tailpipe causes that. You can always change the turbo for a bigger one