DIY: Dual Oil Catch Cans 370Z

wstar · 08-25-2012, 09:45 AM

Don't recirculate the catch can fluids back to the oil pan, it's a bad idea. It's not just oil trapped in them, it's also blowby gas and other vaporized crankcase gasses, which means it's got a high amount of both raw fuel and combustion byproducts (carbon, etc) blended into it. Just smell it once when you're dumping the cans and you'll smell the fuel in it (and as noted above, it picks up a bit of water vapor too).

(Also: you'd be creating a vacuum leak and/or another PCV flow path if you hooked up open drains back to the oilpan, too).

sixpax · 08-25-2012, 03:26 PM

Quote:

Originally Posted by wstar

Don't recirculate the catch can fluids back to the oil pan, it's a bad idea. It's not just oil trapped in them, it's also blowby gas and other vaporized crankcase gasses, which means it's got a high amount of both raw fuel and combustion byproducts (carbon, etc) blended into it. Just smell it once when you're dumping the cans and you'll smell the fuel in it (and as noted above, it picks up a bit of water vapor too).

(Also: you'd be creating a vacuum leak and/or another PCV flow path if you hooked up open drains back to the oilpan, too).

Indeed ... the whole point of doing them to start with was to keep all that stuff out of the motor. Seems a bit defeative to collect them just to put them back in. It is really not that hard to empty them, and only takes a few minutes.

08-25-2012, 09:45 AM	#1 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3596	Don't recirculate the catch can fluids back to the oil pan, it's a bad idea. It's not just oil trapped in them, it's also blowby gas and other vaporized crankcase gasses, which means it's got a high amount of both raw fuel and combustion byproducts (carbon, etc) blended into it. Just smell it once when you're dumping the cans and you'll smell the fuel in it (and as noted above, it picks up a bit of water vapor too). (Also: you'd be creating a vacuum leak and/or another PCV flow path if you hooked up open drains back to the oilpan, too). DEpointfive0 likes this. __________________ 7AT Track Car! Journal thread / Car setup details Last edited by wstar; 08-25-2012 at 09:49 AM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Who's running a catch can?	J. Dub	Forced Induction	58	06-13-2013 07:24 AM
TOP SECRET Oil Catch Cans and Oil Caps	Baker	Drivetrain/Engine	18	08-28-2012 10:12 AM
ARK Muffler Cans really uneven!	ZedSled	Intake/Exhaust	29	08-23-2011 11:26 AM
1000cc oil catch can	Seth G	DIY Section (Do-It-Yourself)	0	03-10-2010 05:44 PM