Page 1 of 2 1 2 LastLast
Results 1 to 10 of 12
  1. #1
    Jordan #94's Avatar
    Join Date
    Sep 2009
    Location
    cayman islands
    Posts
    4

    Can't get RPM's over 7600 no matter what we do on an 09 Ultra 260x

    We recently had our motor rebuilt and the only part we did over that wasn't OEM was the Ferrea valves. After breaking the motor in for about 4 hours, we tested her speed and we got 7980rpms on 37lbs of fuel pressure. The boat is running an aftermarket pulley and air system. We recently carried the ski back to the machine shop to have the valve clearance checked. After this check we went to test it and the most we got was 7780rpms. The s/c belt broke in this time so we thought it was just a problem that the belt was stripped but we put on a new belt and went out again and got the same thing. We tried moving the fuel pressure up and down, we tried to bend the prop, we re-sealed the exhaust, cleaned the intercooler and throttle body...EVERYTHING. We cant get the ski to do more than 7700rpms. The spark plugs in the boat are brand new. Any ideas what the problem could be? NEED AN ANSWER ASAP.


  2. #2
    nicjak's Avatar
    Join Date
    Mar 2008
    Location
    Warragul, Downunder
    Posts
    7,794
    +1
    625
    thats a pretty average rpm but since you have played with the prop i would start back with an oem bend. also if it has a pulley kit it should be around 42-45psi f/p.

  3. #3
    Banned User
    Join Date
    Jan 2009
    Location
    LA/oc
    Posts
    3,911
    +1
    129
    Quote Originally Posted by nicjak View Post
    thats a pretty average rpm but since you have played with the prop i would start back with an oem bend. also if it has a pulley kit it should be around 42-45psi f/p.
    X2.......

  4. #4
    Jordan #94's Avatar
    Join Date
    Sep 2009
    Location
    cayman islands
    Posts
    4
    We just took a brand new 260 prop with no bend in it and the rpms are still down to 7710. We tried to up the fuel pressure to 45lbs and it flooded the motor. We were thinking that the valve clearance might be off. Could that be possible?

  5. #5
    nicjak's Avatar
    Join Date
    Mar 2008
    Location
    Warragul, Downunder
    Posts
    7,794
    +1
    625
    only you will know that... hows the timing? rpms still sound fine to me hope you have an afr on it or she will fry the pistons in secs.

  6. #6
    Jordan #94's Avatar
    Join Date
    Sep 2009
    Location
    cayman islands
    Posts
    4
    We are using the original timing key. From holeshot to mid-range power she feels alright but on top end she feels really lazy. Yes we are running an Afr.

  7. #7
    Banned User
    Join Date
    Jan 2009
    Location
    LA/oc
    Posts
    3,911
    +1
    129
    Quote Originally Posted by Jordan #94 View Post
    We are using the original timing key. From holeshot to mid-range power she feels alright but on top end she feels really lazy. Yes we are running an Afr.
    U making full boost on top end ? Check for leaks pressure test intercooler etc

  8. #8

    Lightbulb

    do you have an aftermarket intake installed?

    i had a similar problem and it turned out to be rubber clogging the intake filter
    from when the supercharger belt broke it was slipping and rubber got stock on the intake filter

  9. #9
    Jordan #94's Avatar
    Join Date
    Sep 2009
    Location
    cayman islands
    Posts
    4
    We found the problem there was a leak in the hose the connection between the intercooler and the throttle body and she is running very good now. Thanks for all the comments guys!

  10. #10
    nicjak's Avatar
    Join Date
    Mar 2008
    Location
    Warragul, Downunder
    Posts
    7,794
    +1
    625
    fp seems very low thats even lower than oem

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. 09 Ultra 260x low RPM Bogging problems after water in the hull
    By moose51 in forum Kawasaki PWC Performance (4-stroke)
    Replies: 5
    Last Post: 01-29-2013, 10:09 PM
  2. Using the proper Octane fuel ????? No Idea What im doing ""97""
    By 1_Fast_SHO in forum Yamaha PWC Performance (4-stroke)
    Replies: 4
    Last Post: 08-18-2010, 03:34 PM
  3. WTB Need rxp hull no matter what shape
    By RXP2 in forum Sea Doo Classifieds
    Replies: 14
    Last Post: 06-05-2010, 09:35 PM
  4. Cool Thing you can do on an IS ski
    By boataddict in forum Sea Doo Open Discussion
    Replies: 3
    Last Post: 08-17-2009, 06:38 PM
  5. Boost - stuck at 7 lbs no matter what ...
    By Vern in forum 4-Tec Performance
    Replies: 8
    Last Post: 08-08-2006, 04:58 PM

Posting Permissions

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