Jump to content
SAU Community

Recommended Posts

OK i dont know much about engines so i will try and explain this to you guys.

I was changing my plugs the other day and when I took the big metal pipe that crosses over where the plugs are in, there was a small amount of oil in the pipe and I am pretty damn sure there shouldnt be.

Do you know what this is from and how bad is it.

Link to comment
https://www.sau.com.au/forums/topic/42634-what-could-this-be-from/
Share on other sites

Sounds like excessive crankcase ventilation.

I understand it as follows - as you wind in more boost or your rings become worn pressure from the combustion process will pass the rings and enter the crankcase. From here the excess pressure breathes from the rocker covers into the induction piping (or in extreme cases from your dipstick hole). Most will get caught in the intercooler but some will make it the plenum. If its only a small amount it should be fine but installing a catch can between the rocker cover vent and the induction piping will prevent most oil from i) entering the combustion process which can cause detonation ii) clogging your cooler and restricting flow. Its an indication your motor is becoming tired but i've also seen tight motors breath heavy if you dial in enough boost.

Worst case scenario would be broken ringlands and/or rings.

Yeh its nothing ben,

Awhile ago when i was running 12psi most of the time it was getting a bit of oil in the throttle body, now that its on standard boost, i havent seen any oil in the last 2 spark plug changes.

Im jus getting a catch can, easiest way to combat it.

i have something related to this in my rb25 silvia i recently bought, the oil is in the intercooler piping from turbo to intercooler (maybe other side, not sure).

from reading this im guessing oil on the engine side of intercooler isnt too bad, but turbo side (unless it came from engine?) is worse?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×
×
  • Create New...