A Quick Note About Oil Catch Tanks and Breathing Systems

1. Colin Saxperience Forum Bum Joined: Jan 2006 Banbury Posts: 4623 Saxo Rally Car Evo 6

   #1 30th July 2009, 10:24

   Anyone can ignore this, i dont mind.
   
   One important thing to say about oil catch tanks, recirculating oil vapours to the inlet and also the whole breather system is this: in laymens terms, oil vapour "waters down" the fuel air mix, thus making it less combustable and contaminates the mixture, mainly the air/oxygen. If you have vapour going back into your inlet (road cars do for emmissions) thats fine as its law etc, but in performance engines e.g. high compression motors, still using this could cause excess crankcase pressure and you then losing all your oil, as liquid always finds a path out of anywhere.
   
   In short, from by passing the vapours into a catch tank / breather, means prior to combustion, the oil vapors are removed, giving longer plug life and improved engine performance from "clean air/fuel" and minimal oily residue in the inlet.

   3 users thanked this post: user_34182, user_35848, Kev_Vtec
2. KamRacing Saxperience Addict Joined: Nov 2006 A farm shed in Aylesbury Posts: 14916 Corolla AE86 Peugeot 205 B18C (in bits)

   #2 30th July 2009, 10:33

   Personally I wouldnt return it to the sump as its mixing with water. Pure oil will not be going back...
   MOT man might notice though...
3. Colin Saxperience Forum Bum Joined: Jan 2006 Banbury Posts: 4623 Saxo Rally Car Evo 6

   #3 30th July 2009, 10:35

   Quote:

   Originally Posted by KamRacing Personally I wouldnt return it to the sump as its mixing with water. Pure oil will not be going back... MOT man might notice though...

   Editted, i dont want to be giving out advice that will mess peoples engines up
4. KamRacing Saxperience Addict Joined: Nov 2006 A farm shed in Aylesbury Posts: 14916 Corolla AE86 Peugeot 205 B18C (in bits)

   #4 30th July 2009, 10:53

   I doubt it would mess up an engine, but it would probably help keep the oil in better condition for longer
5. Colin Saxperience Forum Bum Joined: Jan 2006 Banbury Posts: 4623 Saxo Rally Car Evo 6

   #5 30th July 2009, 10:57

   Quote:

   Originally Posted by KamRacing I doubt it would mess up an engine, but it would probably help keep the oil in better condition for longer

   True. In all honesty, you need to have an engine to warrent the use of a proper setup, but I cant see why (if people are hell bent on it) to make use of a catch tank on mildy modifed engines (like myself) or if people want to keep the combustion sequence cleaner and make it run nicer
6. Colin Saxperience Forum Bum Joined: Jan 2006 Banbury Posts: 4623 Saxo Rally Car Evo 6

   #6 30th July 2009, 13:17

   Maybe sticky this in the question bit above?
7. user_34182 Regular Poster Joined: May 2009 Birmingham Posts: 476 MK2 Saxo VTR(Sold) Skoda Octavia VRS

   #7 30th July 2009, 18:05

   
8. Colin Saxperience Forum Bum Joined: Jan 2006 Banbury Posts: 4623 Saxo Rally Car Evo 6

   #8 31st July 2009, 18:37

   Sticky FTW
9. Kev_Vtec Saxperience Forum Bum Joined: Aug 2009 norfolk Posts: 3116 my drifter M3 rep :D saxo vts eh glad its gone,

   #9 21st August 2009, 21:54

   sorry to ask a daft thing but ive got this airfilter on my saxo
   
   (not a photo of mine but the same)
   ok my oil breather pipe is nipping closed when the pipe is pushed into the airfilter so ive been told for a cheap temp fix get a oil breather filter until i find away how to fix it. what size am i needing? someone said 22mm??? please help.
10. user_15989 Saxperience Forum Bum Joined: May 2007 Posts: 4857

    #10 21st August 2009, 23:37

    Quote:

    Originally Posted by Colin high compression motors, still using this could cause excess crankcase pressure and you then losing all your oil,

    Normally it does the opposite. The inlet tracked where they are plumbed in to are running a vacuum. This actually sucked the gasses out of the engine and the crankcase will tend to drop in pressure compared to venting to atmo.
11. user_16990 Frequent Poster Joined: Jul 2007 Posts: 810 2001 VTS

    #11 21st August 2009, 23:53

    So basicaly oil catch tanks are a good thing as they remove water vapour from the crank/engine? Might have to invest in one me thinks Cheers Colin.