hey all I'm new to this forum so plz take it easy on me if i sound like a noob

I recently got my 4g63 vr4 motor fully rebuilt with wiseco forged pistons have done 5000kms on it and drove it very nicely! for some reason i get smoke from the breathers wen the car is all warmed up and ready to go.. now from what i have heard usually thats not a good sign.. I've done a compression test and was sweet! cylinder 1 was 160psi
cylinder 2 was 163psi cylinder 3 was 160psi and cylinder 4 was 164psi. seems algud to me. took it to workshop and done a leak down test, came back sweet.. i am so worried to drive it because of this problem. anyone got any ideas of wat it could be???

 

You might have a wide piston ring gap which isn't a bad thing, I built mine with huge gaps so it burns more oil than usual but I can run it hard all day long and never worry about the ring ends touching. It will also cause blow-by gases entering the crankcase and will be forced through the breather and even more so under boost.

What I would do is use a single or dual sealed catch can setup routed back into the intake pipe, the turbo will create vacuum under boost and suck the gases out of the crankcase and back into the engine while the cans will catch all the oil/vapors.

 

Hmm.. I'll try that. Is that a known fact? Coz every mechanic I've been to has told me that my motor Is a dud and I've got a long trip soon that I don't want to risk haha

 

i get a bit of vapor at idle with my built motor. i don't think its indicative of issues, just what happens with a built motor that has looser ptw than stock.

 

You need new mechanics. What OKevolution said is true.

 

Yea guess ur right I do need new mechanics haha. So it's ok for the breathers just to sit there and smoke? Also if I do that catch can setup won't it just smoke from the catch can breather?

 

If you don't capture it or re-route it to the intake it the oil vapor will get over everything in your engine bay. The purpose of the catch can is to filter out that oil vapor and release clean air.

 

Not necessarily. I seem to get only water and ethanol vapor. No oil layer building up in the engine bay.

 

Then your car is like mine. No oil. Just "water" that reeks of alcohol (Meth in mine).

OP: Did you check to see if it's oily or the "smoke" you got coming out of the breather is just water?

 

Bumppppppp

 

It's definitely oily as u can smell it too. I just don't Wana spend anymore money on it and find out the motor is a dud.

 

did you come to any conclusion on this?

 

Anytime I have seen visible smoke form a breather (and not vapour) it means a bearing has let go. Seems the heat generated from the trashed bearing burns the oil, causing the smoke.

 

Lol hopefully this wasn't the case. Apparently OP had a long drive.

 

this or any other metal to metal contact causing oil to burn and smoke. smoke from crank case is never good.