Page 1 of 2 1 2 LastLast
Results 1 to 10 of 11
  1. #1

    Is it better to relief cooling water pressure?

    I see many people doing some water routing mods, specially a bypass from one of the head's water outlets.

    On my carbed GP1200R the stock cooling worked fine, but know I'm going 1300 with stock milled head, single pipe, jetworks mod (fercho style, secondary water line), with Dynafly and 05 pump. Keeping in mind reliability, is it better (or even mandatory) to relief some of the added water pressure or leave it stock???

    Does water intrusion becomes a new concern for me? How about cooling effectiveness? with or without bypass.
    Performance?


  2. #2
    CHICKA WAH WAH bren's Avatar
    Join Date
    Sep 2007
    Location
    Cairns, Australia
    Posts
    595
    Quote Originally Posted by chris1200 View Post
    I see many people doing some water routing mods, specially a bypass from one of the head's water outlets.

    On my carbed GP1200R the stock cooling worked fine, but know I'm going 1300 with stock milled head, single pipe, jetworks mod (fercho style, secondary water line), with Dynafly and 05 pump. Keeping in mind reliability, is it better (or even mandatory) to relief some of the added water pressure or leave it stock???

    Does water intrusion becomes a new concern for me? How about cooling effectiveness? with or without bypass.
    Performance?
    what you are listing here is still completely stock, it has no bearing on requirements for re routing a cooling system. Your pipe is stock, your setup is stock.

    enjoy it as it is.


  3. #3
    Moderated
    Join Date
    Oct 2006
    Posts
    3,711
    Quote Originally Posted by bren View Post
    what you are listing here is still completely stock, it has no bearing on requirements for re routing a cooling system. Your pipe is stock, your setup is stock.

    enjoy it as it is.

    Bren

    what about with a fully ported 1300 setup running advanced timing, novi's , vf3's, high comp head etc....

  4. #4
    CHICKA WAH WAH bren's Avatar
    Join Date
    Sep 2007
    Location
    Cairns, Australia
    Posts
    595
    Quote Originally Posted by izz0 View Post
    Bren

    what about with a fully ported 1300 setup running advanced timing, novi's , vf3's, high comp head etc....
    advanced by what? 3 to 4 degrees?

    novis dont make heat, they feed

    high comp head? what 145 ? 165? superjets run this standard

    VF-3"s...they are a reed valve, they only make the engine more efficient.

    porting? or cleaning?

    c'mon, were still talking recreational PWC's here, keep it simple, keep it fun.

  5. #5
    Quote Originally Posted by bren View Post
    advanced by what? 3 to 4 degrees?

    novis dont make heat, they feed

    high comp head? what 145 ? 165? superjets run this standard

    VF-3"s...they are a reed valve, they only make the engine more efficient.

    porting? or cleaning?

    c'mon, were still talking recreational PWC's here, keep it simple, keep it fun.
    While its true those mods will not affect directly the cooling. They do generate more power and spin more rpms on a high pressure pump this results in added higher water pressure inside the cooling system.

    The question is wether added pressure and cooling will add risk of water intrusion and affect performance to a degree that justify adding a bypass.

  6. #6
    Moderated
    Join Date
    Oct 2006
    Posts
    3,711
    Quote Originally Posted by bren View Post
    advanced by what? 3 to 4 degrees?

    novis dont make heat, they feed

    high comp head? what 145 ? 165? superjets run this standard

    VF-3"s...they are a reed valve, they only make the engine more efficient.

    porting? or cleaning?

    c'mon, were still talking recreational PWC's here, keep it simple, keep it fun.
    advanced by advent 94 curve....high comp as in 160 odd with a miller setup ...porting as in ported lowell style

  7. #7
    Moderator DrewNJ's Avatar
    Join Date
    Dec 2005
    Location
    Marlton, NJ
    Posts
    3,716
    +1
    1
    Bypassing one of the head outlets is done mainly to help heat the pipe up. Figure once you lose the cat the pipe will run cooler. Warmer pipes scavange better. However, I never noticed any difference in either my stock 1200 ski or the 1390 ski.
    The other reason was to bring the pressure down. I can only see this being a concern with a big big prop which will flow more water through the cooling system. I also heard it helps with pressure on the big rubber coupler at the U to Stinger connection but I personally never had any issues there.

  8. #8
    32 Valves To Love! Racecar_Dave's Avatar
    Join Date
    Jul 2009
    Location
    Alum Creek
    Posts
    635
    +1
    2
    Why not do it? It's really easy to do and It keeps #3 cooler

  9. #9
    www.2-Stroke-Porting.com
    Join Date
    Dec 2005
    Location
    Lake Havasu City, AZ
    Posts
    135
    Quote Originally Posted by chris1200 View Post
    Keeping in mind reliability, is it better (or even mandatory) to relief some of the added water pressure or leave it stock???

    Does water intrusion becomes a new concern for me? How about cooling effectiveness? with or without bypass.
    Performance?
    Hi Chris,

    My suggestion is put a pressure gauge in the line, between the pump, and the inlet into the exhust manifold. Any time you run over 30 psi you should reduce the pressure to 25 - 30 psi max. Most skis that run low 70's or above need to check pressure. Why risk more chance of water intrusion when 25 psi will flow all that is required for cooling. JMO

    What has happened to other riders is the hose will only leak at WOT by the house clamp and can spray water to the carb area and be ingested. I had one 80+ mph ski burst brand new water hoses. This is also a problem on some Sea Doo skis, and we addressed it with a pressure relief in the line from the pump.

    From the back fitting, on the stock head, use a T, and an inline valve, to control flow overboard. With individual heads - dump #3 overboard.

    Better safe than sorry.

    Lowell

  10. #10
    Quote Originally Posted by LHorning View Post
    Hi Chris,

    My suggestion is put a pressure gauge in the line, between the pump, and the inlet into the exhust manifold. Any time you run over 30 psi you should reduce the pressure to 25 - 30 psi max. Most skis that run low 70's or above need to check pressure. Why risk more chance of water intrusion when 25 psi will flow all that is required for cooling. JMO

    What has happened to other riders is the hose will only leak at WOT by the house clamp and can spray water to the carb area and be ingested. I had one 80+ mph ski burst brand new water hoses. This is also a problem on some Sea Doo skis, and we addressed it with a pressure relief in the line from the pump.

    From the back fitting, on the stock head, use a T, and an inline valve, to control flow overboard. With individual heads - dump #3 overboard.

    Better safe than sorry.

    Lowell
    Very interesting, thats the kind of data I was looking for, I will check the pressure...

    Thanks Lowell!

Page 1 of 2 1 2 LastLast

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Is it better to install a power valve saver or a power valve clip or both?
    By fosgate99 in forum Yamaha PWC Performance (2-stroke)
    Replies: 3
    Last Post: 08-31-2015, 06:16 PM
  2. Is it safe to start the waverunners before you put them in the water?
    By crvtt771 in forum Yamaha PWC Performance (4-stroke)
    Replies: 6
    Last Post: 05-07-2012, 09:01 PM
  3. Is it normal to have a little bilge water after riding on a 2011 FZR?
    By DannyNYC in forum Yamaha PWC Performance (4-stroke)
    Replies: 6
    Last Post: 08-02-2011, 02:26 AM
  4. RXT-IS... is it OK to run the motor out of the water?
    By drober30 in forum 4-Tec Performance
    Replies: 7
    Last Post: 06-16-2010, 10:52 PM
  5. Is it OK to leave your PWC in the water for a week?
    By holdem_up in forum Polaris Open Discussion
    Replies: 3
    Last Post: 07-22-2008, 08:39 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
  •