when driving out and about in my zvh i noticed that occassionally at 3.5krpm i was getting a lot of smoke out of the rear of the car, so i thought turbo and pulled off the throttle.
anyhow i was on a round trip of 200 miles so carried on as the smoke cleared up.
however again it happened on the way back, infact happened twice and even when on boost fully it didn't smoke as such.
when i got home i noticed the ulkhad covered in oil and breather filter was spitting oil out.
it's a GRS breather pot, fed from both ports in rocker cover (burton power alloy one) and to the block breather in the rear.
why is this sometimes happening and why all of a sudden when a couple of weeks back going to and from FITP i had no smoke issues.
i'm pretty sure the smoke was the oil running down bulkhead onto exhaust though.

any ideas welcome

sean

 

Either the breather is insufficient for the boost you're running and needs larger diameter pipe work and outlet, or your engine is starting to breathe a little heavy.

 

outlets are 11mm ID IIRC, filter is just a K&N one.
i suspect the oil may be a little coked up though and overdue an oil change anyhow, maybe the burton cover needs baffles to stop oil surging into the breather holes or that the return to block isn't as smooth as it should be, as the pipe is kinked a bit in places.
just odd that it doesn't happen on boost, just with higher rpms it surges oil to the breather and it isn't coping separating the oil from the vapour too well, maybe i need a bigger breather pot, it isn't the largest by any means @2.5" diameter and 8" tall.

 

update to this, did a compression test and cylinder 4 is down to 135psi, the others are between 150 and 155psi.
clearly a problem, but not so massive that i would have thought it would be kicking loads of oil out.
so i checked oil cooler and pressure tested for leaks and all was good.
cleaned breather pot and pipework and all is now clear (did have quite a bit of mayo in the pipes from hot oil/condensation)
got a bit of fumes coming out of breather filter.
maybe in need of an oil change possibly, been a while since the last one.
lost quite a bit of oil as it landed on exhaust and burnt nicely

 

Boost has nothing to do with your breather system unless you have no piston rings..... which in this case it does sound like Sean!
135psi is shite, even 150psi isnt great maybe on a 80k engine you'd expect to see that sort of reading.
I would say your pressurising the bottom end because of ring/bore wear and forcing oil out your breather system.

 

it's alright lol!
135psi isn't the worst i've ever seen, and was more rev dependant than boost really.
not smoked since i cleaned the breather pipes and pot.
i'm sorting my old daily out and building a properly forged full zetec turbo.
that way i know it's strong enough to last, plus give more mpg's too

 

Boost does have a direct effect on the quantity of blow by that occurs. If we had no blow by then we wouldn't need a breather system at all and if boost pressures had no effect on the breather, there would be no reason to fit an uprated breather oil seperator and catch tank. Been there and done all this research before, 10 years ago.