Smoking on initial wot

[cat007]

Hi all

What would cause blue smoke to come out once at full boost but then it goes away after a second?

Turbo seals/rings? Piston rings? Stem seals?

[cat007]

Have also noticed that it seems to do it at idle once it's warmed up too.

Took the plugs out and they aren't oiled so maybe turbo turbine oil seal?

[Shrike]

When you did the springs you replaced the valve seals right?

[Crucible]

Sounds like turbo but generally itll be more white than grey.

Do you have good crankcase ventilation and drain? Only way to be certain is drop front pipe and see if there is oil residue in the exhaust housing.

[cat007]

When you did the springs you replaced the valve seals right?

I didn't. But I did replace them when I rebuilt the engine about 10kms ago....

[cat007]

Sounds like turbo but generally itll be more white than grey.

Do you have good crankcase ventilation and drain? Only way to be certain is drop front pipe and see if there is oil residue in the exhaust housing.

I have breather hoses from each cam cover to a big breather box that's vented to atmosphere. Not ideal, I know..

Here's a wee vid. Not sure if this helps diagnosis?

https://www.youtube.com/watch?v=MB9eNME ... e=youtu.be

[cat007]

Also I should note that it doesn't smoke at idle when the engine is cold, or when you first start the engine. Only once it's warm does it start to smoke...

[Mr Ree]

You should plumb back your catch can to the intake pipe between the filter and turbo.

The system needs vacuum on it to work efficiently.

I would imagine the smoke would be due to oil pressure being fairly high under the WOT dyno run, and a bit of oil is forcing its way past the turbo seal.

It might do this while you drive but is less apparent.

[cat007]

You should plumb back your catch can to the intake pipe between the filter and turbo.

The system needs vacuum on it to work efficiently.

I would imagine the smoke would be due to oil pressure being fairly high under the WOT dyno run, and a bit of oil is forcing its way past the turbo seal.

It might do this while you drive but is less apparent.

Yeah - I know. I really should plumb it back into the intake. Maybe that's something I'll look into doing.

If there was oil forced past the turbine o-ring then wouldn't it have been burnt off shortly there-after? Or is it something that once it's done it, it'll happen all the time?

[Crucible]

Also I should note that it doesn't smoke at idle when the engine is cold, or when you first start the engine. Only once it's warm does it start to smoke...

If thats the case it points the finger more towards the turbo. The exhaust housing is still coldish on start up and not hot enough to start burning oil off sitting around turbine.

Would still pay to check inside exh housing. Running vac line like Ree suggests would help also. Those filters on most cans you see block up quite easy which adds to the problem.