Results 1 to 9 of 9
  1. #1

    Rotax 951 stuck at high revs!!!

    Fired up my 99 XP limited for the first time after replacing all of the lines, and it fired right up. Only problem is goes straight to max rpm and never comes down! I pulled off the DESS and it just keeps on revving. Only way to stop it was yanking the plug wires.

    The butter flys inside the carbs are not stuck and open, and close with the throttle lever. Im stumped as to why it would stay on with the DESS pulled and keep revving to max rpm with the throttle closed.

    Need some help guys.


  2. #2

    Join Date
    Aug 2008
    Location
    Eastern NC
    Posts
    223
    +1
    8
    The fact that you replaced the lines would leave me to believe you may have one on wrong. Check and double check the hose routing.

  3. #3
    All lines have been checked and are where they are supposed to be. Although it still doesn't explain why the engine was still running after the DESS was pulled. As that could be very dangerous on the water ive got to fix this issue before i head to the lake.

  4. #4
    SURFnTURF's Avatar
    Join Date
    May 2007
    Location
    Australia
    Posts
    878
    +1
    11
    Your idle is set too high (maybe not enough slack in the cable adjustment) and /or the low speed adjusting screws are too lean.
    Needs to be 1.5 turns out from seated position

  5. #5

    Join Date
    Aug 2008
    Location
    Eastern NC
    Posts
    223
    +1
    8
    Well as far as the running after DESS is pulled, it would either indicate a faulty dess post, mpem, or the engine is dieseling.

  6. #6
    xxx2's Avatar
    Join Date
    Oct 2006
    Location
    panama city bch, Fl
    Posts
    421
    +1
    35
    Next time grab a handful of throttle if it doesn't die with the lanyard pulled. You have a lean condition, possibly a air leak. The runaway engine gets so lean/hot that it does not need a spark to ignite so when you pull the lanyard it doesn't matter either hit the choke or cool it down by hitting the throttle next time and it will die. It won't run away like that in the water..with a load on it, however being its running lean it will probably melt a piston when you put it under load unless corrected.

  7. +1 by:


  8. #7
    SELF27's Avatar
    Join Date
    May 2013
    Location
    Austin, TX
    Posts
    202
    +1
    16
    Quote Originally Posted by xxx2 View Post
    Next time grab a handful of throttle if it doesn't die with the lanyard pulled. You have a lean condition, possibly a air leak. The runaway engine gets so lean/hot that it does not need a spark to ignite so when you pull the lanyard it doesn't matter either hit the choke or cool it down by hitting the throttle next time and it will die. It won't run away like that in the water..with a load on it, however being its running lean it will probably melt a piston when you put it under load unless corrected.
    +100 common on 951 motor. Will scare the crap out of you! Surprise pulling plug caps stopped it! Usually doesn't work.

  9. #8
    The 951 is picky on idle speed. Set it at 2800 rpms out of the water

  10. #9
    flyin' the friendly skies airbornexp's Avatar
    Join Date
    Aug 2007
    Location
    Mahomet, Il. USA
    Posts
    6,004
    +1
    163
    You have an air leak... That is a lean run away if it's running after the dess is pulled.

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Polaris Virage 2001 Sticking at high revs.
    By pogle63 in forum Polaris Tech Tips and Info
    Replies: 3
    Last Post: 07-20-2015, 07:07 AM
  2. 96 GTX cuts out at high RPM - rev limiter?
    By demne in forum 2-Stroke Performance
    Replies: 4
    Last Post: 05-30-2015, 08:48 PM
  3. High Revs at idle
    By rcapone in forum Yamaha PWC Performance (4-stroke)
    Replies: 3
    Last Post: 12-29-2012, 12:46 PM
  4. High revs at idle
    By MARK_LEGG in forum 4-Tec Performance
    Replies: 13
    Last Post: 08-17-2009, 10:02 AM
  5. High Revs at idle
    By tonkatiger in forum Polaris How To & FAQs
    Replies: 14
    Last Post: 07-02-2008, 10:01 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
  •