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Did a rebuild and added the a catch can on the valve cover to intake hose. I am catching this fluid in the catch can, and it is getting worse? Oil is clean and looks good with no leaks, coolant is full with no signs of exhaust gases/no excess pressure, compression is good and even all across the cylinders, rechecked timing and it is good? As this gets worse, it's starting to have rough running issues, no codes? Spark plugs are clean, and if anything, I might be concerned it is running lean? Coolant is green, and there are no fluids this color, and it has an awful smell, almost like the old safety clean carburetor cleaner that use to come in the yellow 5 gallon buckets? this is the crazy part, it looks to be blowing out of the turbo intake into the catch can, as the line out of the PCV/valve cover looks to be dry, and there is definitely fluid at the turbo/intake hose. Boost side of turbo is dry. I am experiencing some turbo flutter, also with a stage 2 tune
Last edited by 2008MiniS; Nov 6, 2018 at 09:29 AM.
Your OCC is on which "intake" --- manifold or turbo (assuming N14)? With oil in the turbo's fresh air inlet and a dry PCV port, there's probably positive pressure in the crankcase. Could also be a shot turbo --- is there any "wobble" on the compressor wheel? Should be ZERO wobble --- any direction. With engine idling, try unseating the dipstick --- engine idle should get "rough" and air should flow into the dipstick tube. Same test for the oil fill cap.
What did your "rebuild" consist of? Old valve stem seals can cause positive crankcase pressure, so can a bad PCV in the valve cover.
Your OCC fluid looks normal for the manifold port --- lotsa condensation and a little oil. OCC fluid from the turbo port is typically much lower in quantity, compared to the manifold port.
Your OCC is on which "intake" --- manifold or turbo (assuming N14)? With oil in the turbo's fresh air inlet and a dry PCV port, there's probably positive pressure in the crankcase. Could also be a shot turbo --- is there any "wobble" on the compressor wheel? Should be ZERO wobble --- any direction. With engine idling, try unseating the dipstick --- engine idle should get "rough" and air should flow into the dipstick tube. Same test for the oil fill cap.
What did your "rebuild" consist of? Old valve stem seals can cause positive crankcase pressure, so can a bad PCV in the valve cover.
Your OCC fluid looks normal for the manifold port --- lots a condensation and a little oil. OCC fluid from the turbo port is typically much lower in quantity, compared to the manifold port.
N14, Back port on valve cover to intake manifold is capped off. This is through the PCV to turbo intake hose. New JTMC S42 turbo in April with all new oil lines, new rings, bearings, head removed/checked, and cleaned with new seals. New HPFP, New injectors/coils, and valve cover. New timing chain, solenoid. No excess crankcase pressure. I suppose the cc was getting a little over 3/4 full and maybe it was splashing around and got into the intake hose? I've just been trying to figure out where all this liquid is coming from? It's non-flammable whatever it is, and no signs of anything like this anywhere in the cylinder head or valve cover.
OK, so after some looking around, this is exactly what is normal to catch in the catch can! so, what got in my intake probably was from the CC getting too full. The weather is all over right now, so the water vapor really has increased probably. Scary to think that crap is getting blown back into the intake? Now, just to figure out why it started to run rough? Gonna try some one step colder plugs that I should probably be using anyway? Then chasing a ghost? https://www.northamericanmotoring.co...cs-tuning.html
N14, Back port on valve cover to intake manifold is capped off. This is through the PCV to turbo intake hose. New JTMC S42 turbo in April with all new oil lines, new rings, bearings, head removed/checked, and cleaned with new seals. New HPFP, New injectors/coils, and valve cover. New timing chain, solenoid. No excess crankcase pressure. I suppose the cc was getting a little over 3/4 full and maybe it was splashing around and got into the intake hose? I've just been trying to figure out where all this liquid is coming from? It's non-flammable whatever it is, and no signs of anything like this anywhere in the cylinder head or valve cover.
Q: If your back port to intake manifold is capped off, where is the crankcase getting it vacuum?
A: It isn't --- pressure is building in the crankcase causing oil to be forced thru the turbo bearings and into the compressor.
This can be confirmed by inspecting the PCV to turbo hose (OCC output) --- if it's dry and there's still oil in the turbo air inlet, where else can oil be coming from?
Q: If your back port to intake manifold is capped off, where is the crankcase getting it vacuum?
A: It isn't --- pressure is building in the crankcase causing oil to be forced thru the turbo bearings and into the compressor.
This can be confirmed by inspecting the PCV to turbo hose (OCC output) --- if it's dry and there's still oil in the turbo air inlet, where else can oil be coming from?
I think there would be some vacuum at the turbo side pcv port since it the turbo is creating a negative pressure point in front of it by sucking air. Cooler ambient temperatures will cause a delayed warming of the engine, causing more condensating of the gases in the occ. The water is a byproduct from the burning of hydro/carbon based fuels and is slightly acidic. My concern with the plugging of the rear pcv port has to do with the vavle cover design. If I understand it correctly there are four things going on with its design. One and two are the one way valves at each port discharge point. This prevents back pressure from entering the valve cover under certain conditions. Three and four is the combined vavle located between the two ports. It appears that the bottom portion of this valve directs the flow of gasses to either port again depending engine conditions. The top portion of the valve limits the amount of vacuum you can generate inside the valve cover and there for the engine. When this valve fails you see the oil fill cap being very hard to remove as a result of the high vacuum. This also results in gasket and seal failure from them being sucked into the engine. Further to my concern is that by capping the rear intake pcv port you short circuit half of this system and potentially leave this acidic water to condence in the engine. This acidic water overloads the engine oil which has additives to combat it but oil can only do so much once that additive is used up. I suspect some rear blocked systems do work but this may be a result of the directional/vacuum limiting valve has failed and is allowing gasses to be removed by the turbo port at all times. I'm no expert on the n14 engines but have been around car and boat engines my whole life.
There is an awful lot of write-ups in here and other forums about blocking the rear port to intake manifold off, and it was recommended by a popular vendor in here to do along with my modifications. Heck the dealer knew exactly what I was doing when I ordered the caps.
I mentioned, i jumped the gun on the fluid in my intake hose, I believe it was from the cc being full and it made it's way into the turbo intake hose. It was the same fluid in the cc, which is mostly water. I confirmed this with a turbo rebuilder, that there is no way for coolant to come from the turbo into the intake(which is kind what i was thinking, since the turbo would be sucking in air, not pushing it back out). I believe the rough running is a result of my ebay vanos solenoid, or a faulty sensor, and it just happens to not be throwing a code. It is doing something very similar to when my solenoid failed before. It starts up fine cold, but starts running rough as it warms, because the timing isn't changing like it should. I just panicked when I keep seeing how much the catch can actually catches. Further research points to this being normal, especially this time of year. if i had excessive crankcase pressure, it would most certainly be blowing gaskets, which is why the engine was rebuilt in the first place. the rings were shot.
All excellent points, my post was in no way a critique of your work. All ideas and trials, errors and successes are what allows us to keep improving our cars. Keep us posted on your build and occ. Regards 😎
I figured the trick is to Google " normal contents of oil catch can". Just "catch can" showed mostly people who put on a catch can with a blowed head gasket.
