Results 1 to 8 of 8
  1. #1
    EH Team Water Pig's Avatar
    Join Date
    Oct 2007
    Location
    St. Catharines, Ontario, CANADA
    Posts
    773
    +1
    66

    RXP-X Crank Case Vent Tube Question

    When installing the 4” Kanoflex intake some guys are running the crank case vent tube to a catch can and then calling it a day.
    In stock form the vent tube is routed into the air intake to the supercharger.
    Les Cooke at Seadoo Centre sells a performance 4” Intake Filter Coupler that also has a fitting for the cc vent tube.
    Is one vent tube application better than the other?
    If so, can someone explain their thoughts on why?
    Last edited by Water Pig; 04-10-2009 at 05:27 PM. Reason: Catch Can Question


  2. #2
    MPower's Avatar
    Join Date
    May 2005
    Location
    Raleigh, NC
    Posts
    3,338
    +1
    121
    From what I've read there isn't much need to run the line back into the intake unless you ride in the ocean. In that case the oil can help lube the charger. Then again, I never found any substantial trace of oil in my stock intake, so not sure how much oil even comes out on a stockish motor.

  3. #3
    SeaGoat's Avatar
    Join Date
    Jun 2008
    Location
    Jacksonville, N.C.
    Posts
    2,214
    +1
    2
    I found a trace of oil film on the hose coming from the supercharger but just barely enough to discolor a rag.

  4. #4
    EH Team Water Pig's Avatar
    Join Date
    Oct 2007
    Location
    St. Catharines, Ontario, CANADA
    Posts
    773
    +1
    66

    Catch Can or Not

    That makes sense. Especially since Australia is surrounded by salt water.
    Has anyone ever examined/tested crank case pressure/horsepower issues.
    I'm told that the intake draw may assist more in bringing the cc pressure down and therefore not rob your machine of any potential horsepower.
    Does that make any sense?

  5. #5
    SeaGoat's Avatar
    Join Date
    Jun 2008
    Location
    Jacksonville, N.C.
    Posts
    2,214
    +1
    2
    It makes sense to me. Why else would they install it? It also reduces pumping losses since the engine actually acts like a big air pump and the pressure in the cc costs power.

  6. #6
    GTXX's Avatar
    Join Date
    Jan 2006
    Location
    NW, GA
    Posts
    1,776
    Quote Originally Posted by Water Pig View Post
    That makes sense. Especially since Australia is surrounded by salt water.
    Has anyone ever examined/tested crank case pressure/horsepower issues.
    I'm told that the intake draw may assist more in bringing the cc pressure down and therefore not rob your machine of any potential horsepower.
    Does that make any sense?
    I agree that it helps lower crankcase pressure from some previous experience on a drag car and argued the point a little, many will say it doesn't matter. Mine is and always will be connected and I ride freshwater only. I made a few of the couplers that you described that Les Cooke has for 3" when I did my fresh air in 2006. I bought the material to make a few 4" but never did.

  7. #7

    Join Date
    Nov 2006
    Location
    Delray Beach, Florida
    Posts
    423
    +1
    1
    Crankcase blow by is spent gas void of oxygen. When you put it back into the fresh air intake, you are contaminating the charge. OEM has to do it that way to be environmentally friendly. IE: if you over fill your oil, and it blows out the catch can vent, it will end up in the lake. OEM style makes you burn it off rather than polute. The HP benefit of venting to a catch can is always better than the HP benefit of the minute amount of crankcase pressure you will relieve, and in a 4 inch inlet tube, there is very little pressure differential.. if there was a substantial pressure drop, then it would be beneficial to go 5 inch !!! That is just from my personal experience.

  8. #8
    EH Team Water Pig's Avatar
    Join Date
    Oct 2007
    Location
    St. Catharines, Ontario, CANADA
    Posts
    773
    +1
    66

    Catch Can or Not

    Thanks for your comments.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. 2009 GTI 155 Crank case vent question??
    By Unit44 in forum 4-Tec Performance
    Replies: 1
    Last Post: 06-29-2015, 03:20 AM
  2. Rxp 215 stage 1, vent tubes ???
    By BIMMER09 in forum 4-Tec Performance
    Replies: 2
    Last Post: 04-05-2011, 04:36 PM
  3. crank case vent not fully drilled open!!
    By born riding in forum Kawasaki PWC Performance (4-stroke)
    Replies: 3
    Last Post: 07-03-2008, 03:17 PM
  4. crank case vent hole "casting" flaw
    By halfassjack in forum Kawasaki PWC Performance (4-stroke)
    Replies: 20
    Last Post: 05-13-2008, 11:09 PM
  5. crank case vent fitting
    By halfassjack in forum Kawasaki PWC Performance (4-stroke)
    Replies: 60
    Last Post: 05-05-2008, 08:07 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •