Page 1 of 3 123 LastLast
Results 1 to 10 of 23
  1. #1
    overboost's Avatar
    Join Date
    May 2018
    Location
    Earth
    Posts
    128
    +1
    5

    2019 RXTX 300 will not rev past 7500? WTF

    So I have a 19 RXTX and it does have some mods to it, only has about 14 Hrs on it now....will list mods and things I have done to try and find the problem

    mods , Riva RRFPR( set @ 58 PSI) supertech springs and TI retainers , IMUK , Riva thru hull exhaust , exhaust spacer , rear air intake 4" veloicty stack / with outer wearz cover , Lucky 13 cone no spacers , JL Perf 3 degree pump wedge , dash pac( boost and AFR , JLP tune 9K rpm and 650 cc injectors

    so in water test 1/2 tank fuel only resulted 70 mph @ 7400-7500 RPM and 11.5 to 12 PSI boost ( cool weather 67 out ) with rear ski hole open to help hull breathe

    out of water on trailer on hose free rev, still 7400 - 7500

    fuel pressure stays @ 58PSI does not really move

    oil is 1/2 way between marks

    prop is stock

    swapped a buddys ECU and injectors ( 8550 RPM tune ) 1 st rev can get 8400 8500 , then after that will only see 7400-7500 ( on trailer on hose )

    checked hoses from Sc to IC and IC to TB , all tight ...

    checked exhaust / all tight

    removed intake manifold to check IMUK for leak

    did have cam timing retarded , moved it back to OEM position

    going to check the SC slip next ...

    fresh 93 fuel

    and the big mistake on my part was when I got ski, didn't water test it as it was low HRS and everything seemed great as it was very new and has 12 or so hrs on it , runs smooth on hose , so not sure if this was a issue prior to modding over winter or some of mods.... if the lucky 13 cone is killing some RPM's I can see that.... but not while on trailer out water on hose, so thats likely to come off and back to stock soon

    so chime in if you know whats wrong or other advice on what this problem could be.

  2. #2

    Join Date
    May 2005
    Location
    Fort Myers
    Posts
    910
    +1
    46
    Sounds like your tune isn't working and your on the speed limiter of 69

    Good luck

  3. #3
    www.eastcoastpwc.net Scott's Avatar
    Join Date
    Jul 2007
    Location
    NJ
    Posts
    8,757
    +1
    591
    Next time the intake manifold is off, check the cam timing. Some known cases where the gear on the crank slipped.

  4. #4
    overboost's Avatar
    Join Date
    May 2018
    Location
    Earth
    Posts
    128
    +1
    5
    I swapped in another ECU from another ski ( known to have 8550 rpm limit and usually runs 81+ mph ) ... so not thinking its ECU related

  5. #5
    overboost's Avatar
    Join Date
    May 2018
    Location
    Earth
    Posts
    128
    +1
    5
    Quote Originally Posted by Scott View Post
    Next time the intake manifold is off, check the cam timing. Some known cases where the gear on the crank slipped.
    ok... will add that to list of items to check... thx

  6. #6
    NitroFish300's Avatar
    Join Date
    Sep 2019
    Location
    Marshall TEXAS
    Posts
    67
    +1
    5
    dead cylinder? I had a spark plug tube leak oil onto the plug causing a misfire with Similar symptoms

  7. #7
    overboost's Avatar
    Join Date
    May 2018
    Location
    Earth
    Posts
    128
    +1
    5
    Quote Originally Posted by NitroFish300 View Post
    dead cylinder? I had a spark plug tube leak oil onto the plug causing a misfire with Similar symptoms
    I even swapped coils over from a buddys RXTX 300, ( his is good ) still same , with his ecu and coils and injectors in....first couple of revvs... i would see 8200 , maybe 8500 ( he has 8550 limiter ) , but then will not go above 7400-7500

    all cylinders are firing / no oily / bad plugs they have color on them .. looks to be good burn

  8. #8
    moparguy's Avatar
    Join Date
    Sep 2016
    Location
    Niagara Falls, Ontario
    Posts
    1,934
    +1
    385
    Faulty knock sensor? Do you have ability to log?


  9. #9
    overboost's Avatar
    Join Date
    May 2018
    Location
    Earth
    Posts
    128
    +1
    5
    no.....but do have access to one that is good....would a bad one set off check engine light?

  10. #10
    NitroFish300's Avatar
    Join Date
    Sep 2019
    Location
    Marshall TEXAS
    Posts
    67
    +1
    5
    Have you pulled the hose from the intercooler to the TB while on the hose to ensure it not ingesting water?

Page 1 of 3 123 LastLast

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. 2019 RXTX 300 Cracks
    By RXTX-RS in forum Sea Doo Open Discussion
    Replies: 25
    Last Post: 03-14-2020, 08:34 AM
  2. 2019 RXTX 300 High Altitude Impeller
    By Tom Sawyer in forum 4-Tec Performance
    Replies: 15
    Last Post: 11-20-2019, 03:07 PM
  3. 2019 rxtx 300
    By usamps in forum 4-Tec Performance
    Replies: 40
    Last Post: 07-11-2019, 12:09 PM
  4. 2019 rxtx 300 stock rpms speed
    By holeshot1 in forum 4-Tec Performance
    Replies: 0
    Last Post: 06-15-2019, 03:38 PM
  5. 2019 rxtx 300 impeller selection
    By holeshot1 in forum 4-Tec Performance
    Replies: 10
    Last Post: 05-07-2019, 08:30 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
  •