Crankcase Venting Question

[FJota]

12HT
The valve cover has a port to vent to the turbo intake pipe, but were does it draw clean air in to the crankcase? With out an intake the turbo will pull oil from the engine. (correct ?)

 

[bigbrowndog]

12HT
The valve cover has a port to vent to the turbo intake pipe, but were does it draw clean air in to the crankcase? With out an intake the turbo will pull oil from the engine. (correct ?)

No oil only fumes unless you are getting oil blowback past your rings you should have blue smoke then.

 

[FJota]

I don't think that blowby is my problem. If I take the cap off there is no visable smoke or wind.

I am getting oil at my turbo. Which has been rebuilt.

Any ideas?

 

[bigbrowndog]

Well if you were getting blowby you should know it as it pressureises the sump and forces fumes into the rocker area as well as oil mist also fumes can come out the dip stick tube when the stick is removed.The motor would be using oil and blowing blue smoke. How much oil is the motor using? How much oil is coming out the turbo? Do you think a seal in the turbo is responsible?Is there much oil in the high pressure crossover?

 

[FJota]

I just had the turbo rebuilt, the blowby just dosent seem bad. It has been parked for about 6 months. Last august I took it on a trip and did not add any oil. I don't see any smoke (blue) under normal driving. I can see oil at the rubber coupler between the turbo (pressure side) and the high pressure crossover.

Has new air filter aswell

 

[mallred]

With my 80 3b there is no indication of Crankcase pressure when I have the CC vent tube connected to the air intake pre turbo but when disconnected it has excessive blowby when Hot, minnamal when cold out the oil filler and cc tube, also collects in the turbo and further. Try and disconnecting your vent and see what happens, Fresh oil seems to slow down my consumption, this will do until I do a rebuild or replacement of the engine. other than that it runs strong. compression 370-380 range. I do no see blue smoke while running the truck but the oil does disappear.

 

[FJota]

Thanks for the tip. I think that I am going to put a draft tube on the valve cover vent and block off the pipe to the turbo intake and see if it makes a difference.