condensation in crankcase ventilation

[quattro-nick]

hi guys
i use a mann provent 200 for crankcase ventilation and it works realy great
there is in the catchcan no oil,only candensation but i think this is normal
but my question is,there is on the underside of the catchcan a draintube which i connected to my sump so when i have a lot condensation it goes to the sump in the engine oil
on the other side,there will also be condensation with a normal crankcase ventilation so shall l leave it this way or should I better block the drainpipe

thanks
nick

[K Simmonds]

Personally I don't like condensation going back into the oil so I don't have a return to sump with my catch tank set up, I simply empty it every 2 tanks of fuel. That said most folk on here who run catch tanks do return it to the sump so it can't do any real harm.

[quattro-nick]

the problem is that I usually drive many short distance because this is a hobbycar so more condensation but with this high power engine i replace my oil every 5000 km so i think the condensation will not be a problem

[AndyP]

Having seen what comes out of my catch can, I'm glad I have it, I'd not want it going back into the engine.

[quattro-nick]

from how long driving is this?

[AndyP]

Te picture is quite old, but I'd guess at 6months and around 3-4000miles.

I don't have to empty the catch can very often, but what does come out looks nasty!!

[popdemonic]

Provent 200 didn't work well on my old and new AAN engine atleast on my car.

[quattro-nick]

works well for me,total no oil in catchcan and inlet

[K Simmonds]

Having seen what comes out of my catch can, I'm glad I have it, I'd not want it going back into the engine.

That's what mine looks like as well, as you say I rather not have it returned too the sump.

[Thuppu]

Thats just oil/water suryp. If returned to sump, the water will evaporate when oil is hot enough.

[Mcstiff]

Thats just oil/water suryp. If returned to sump, the water will evaporate when oil is hot enough.

I've debated this on other forums; I'm of the opinion that the catch can simply increases the volume of air in the system and condenses more moisture as a side effect. The non-returning catch can magnifies the "problem" because it collects the condensate from every heat cycle without allowing it to evaporate (by design, the liquid is trapped in the can). This also makes for increased emulsion since the hot crankcase fumes are likely to be cooled by the liquid in the catch can and condense/mix.

*My catch can does not return because I did not want to deal with the plumbing

[quattro-nick]

okay,i will let my oil return to the sump open

[popdemonic]

FYI,i'm running the Provent 200 for years but seems the blow by with oil/moist still vented back to
the engine.originally,the provent 200 vents has inlet on the upper chamber and outlet on the lower port.
i think by its design caused the separator couldn't catch the extra blow by
from the high boost engine.i decided to reverse the input and output and connect the drain port back to sump.
so far so good,no more oil vapour gets back into the intake.only downside is the blow by is not filtered before drained back to sump.I will need the swirl pot in the future anyway.i'm currently running 30psi
of boost and that might be the causes of extra blow by.FYI.