So misguided it's actually laughable.

Condensation is a by product of heat cycling.........Once the engine in up to operating temp any condensate in the oil evaporates off.
Where does anyone (or any manufacturer) recommend more frequent oil changes in cold weather??

FYI this is how the factory system works - it flows in one direction off boost & reverses on boost....

[IMG]http://i49.photobucket.com/albums/f273/hardknoxlife/IWSTI%20Thread/StockUnderVacuum.gif[/IMG]

Crankcase ventilation ON boost

[IMG]http://www.microabacus.com/images/crankcaseandrockercovervents_under_boost.gif[/IMG]

[url=http://www.waynesgarage.com/docs/oil.htm]Automotive Engine Oil, How often should you change it?[/url]

I pluged a inline fuel filter to my crank breather, during cold start, it collected brown sludge immediately, and evaporated after 10min driving.

Attached is my old set up, to reduce flow resistance, i runs straight breathers now.

I also have a question, if oil is pumped to cylinder head, would it be on constant positive pressure unless engine breaking?

Without getting technical. Block the PCV off. Crank and head breathers to catch can,
can vent to atmosphere via a hose that runs under the car. Don't just put filter on the top and vent in the engine bay as you'll get fumes and smell it in the car. It's not pleasant (unless it Motul 300V which has an amazing smell lol). Then have a -10 return to sump. You can put an NRV in it if you wish. I never have and that set up has worked flawless for me for a number of years.

Please get technical. Would like to learn more.

Thanks for everyone's input so far. I have searched this topic I just couldn't find threads which answered all my questions.

[QUOTE=dazdavies;820326]Without getting technical. Block the PCV off. Crank and head breathers to catch can,
can vent to atmosphere via a hose that runs under the car. Don't just put filter on the top and vent in the engine bay as you'll get fumes and smell it in the car. It's not pleasant (unless it Motul 300V which has an amazing smell lol). Then have a -10 return to sump. You can put an NRV in it if you wish. I never have and that set up has worked flawless for me for a number of years.[/QUOTE]

I should use a catch can. It pushs more oil out with a bigger turbo now.

U reckon join both breather shouldn't have problems? Plz bring some theory if u have time. My mate with a built evo8, compreession and leak down test were good, but crankcase gas is enough to pop out dip stick. Might be design of the engine?

using the Perth-WRX mobile app

This also prevents the build up and use of oil.

[ATTACH]14593[/ATTACH]

Just did this experiment at work, during smoko of course...

So with pure vacuum there is no liquid movement between the vessels (vessel on left is the catch can) Catch can collapses under vacuum. With a partial break in vacuum at the vessel on the right(sump) the catch can easily sucks the water up from the sump.

So catch can with vacuum and draining back to sump is a no no. If it had a breather to atmosphere (dazdavies, Gordon) it will work but then there would be no point running the pcv to it then would there...

I wouldn't want to rely on a nrv to prevent oil sucking back up through the sump, I work with them everyday they fail and pass regularly.

[QUOTE=s20525xxx;820324][COLOR="Red"]1.[/COLOR][url=http://www.waynesgarage.com/docs/oil.htm]Automotive Engine Oil, How often should you change it?[/url]

[COLOR="red"]2.[/COLOR] I pluged a inline fuel filter to my crank breather, during cold start, it collected brown sludge immediately, and evaporated after 10min driving.

[COLOR="red"]3.[/COLOR] Attached is my old set up, to reduce flow resistance, i runs straight breathers now.

[COLOR="red"]4.[/COLOR] I also have a question, if oil is pumped to cylinder head, would it be on constant positive pressure unless engine breaking?[/QUOTE]

1. 4000miles is just shy of 6500km, Extremely cold weather is -20 degrees C

2.Like I said, it's condensate from the engine cooling down & pulling moisture from the air - it is worse on humid days, it is completely normal & does no harm.

3. OMG......how did you expect the crank case gases to pass through that with that closed cell foam packed in there so tightly??

4. Oil is always pumped to the heads when the engine is running. The blow-by gas volume increases with rpm & boost. There is always some blow-by if the engine is turning regardless whether its at idle, cruise, on boost or on over run.

[QUOTE=s20525xxx;820333]I should use a catch can. It pushs more oil out with a bigger turbo now.

U reckon join both breather shouldn't have problems? Plz bring some theory if u have time. My mate with a built evo8, compreession and leak down test were good, but crankcase gas is enough to pop out dip stick. Might be design of the engine?

using the Perth-WRX mobile app[/QUOTE]

My best mate in the UK had exactly the same issue with his Norris Designs Built Evo 6. I know its off topic but it's a lovely car. I'm sure you'll appreciate this work that's gone into this.

[img]http://www.scoob.co.uk/craigsevo/evo1.jpg[/img]
[img]http://www.scoob.co.uk/craigsevo/evo2.jpg[/img]
[img]http://www.scoob.co.uk/craigsevo/evo3.jpg[/img]
[img]http://www.scoob.co.uk/craigsevo/evo4.jpg[/img]
[img]http://www.scoob.co.uk/craigsevo/evo5.jpg[/img]


Back on topic.

If you want to you can Tee all the breathers together so you just have one inlet to the catch can. I'd only use a baffled can as the un baffled ones don't do much. Feeding back to the inlet is a waste of time in my eyes but I understand that you may not have a choice to be road legal but it's easy to swap.

That's main reason mine is plumb back in being early twenties cops don't need any extra help slapping out stickers


But my can is baffled and I don't get any oil in my intake system well havnt yet anyway



using the Perth-WRX mobile app