Results 1 to 6 of 6
  1. #1

    Unhappy 96 SL780 Fuel out the exhaust!!!!!!???

    Hi, I am new here and just got a 1996 SL780 from a friend. Its firing but revs really high, battles to start and has fuel coming out the exhaust...? I have never owned 1 of these and have no idea what it could be...!!!
    The limp mode also kicked in but once i disconnected the MFD, the ski reved up and seems to free rev with no pull of the throttle.

    Any help would be greatly appreciated, thanks


  2. #2
    Click avatar for tech links/info, donation request K447's Avatar
    Join Date
    Jul 2007
    Location
    near Toronto, Canada
    Posts
    36,587
    +1
    1,272
    Welcome

    Did the fuel coming out of the exhaust reduce when the MFD was disconnected?
    How much fuel are we talking about?
    Is this on the trailer, or in the water?

    Does the MFD display actually work?
    Any red lamp or messages?
    Low oil, Low Ful, HOT, etc...

  3. #3
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
    Join Date
    Jul 2007
    Location
    Cedar Rapids,Iowa
    Posts
    6,381
    +1
    23
    Start with running a compression Check.

  4. #4
    MFD works but with half a tank of fuel, still saying low fuel and low oil and the red light is flashing. Its a fair amount of fuel and i notice the 3rd cylinder( closest to the rear of ski) has loads of fuel in even after firing it up. The other 2 cylinders seem normal. All this is on the trailer, not in the water.

    I will do a compression check on Monday...!! That was my next on the 'to do' list...

    Thanks for your help so far, lets hope i can sort this out sooner rather than later.

    Cheers

  5. #5
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
    Join Date
    Jul 2007
    Location
    Cedar Rapids,Iowa
    Posts
    6,381
    +1
    23
    If you have a burnt piston,you'll be pumping fuel out the exhaust.If you have the ski close,stick a finger over the sparl plug hole and see if you have any pressure at all.Shouldn't be able to hold it. Will give you a general idea. But do the test with a gauge when you can.

    I sure none of the 650-780's had a limp mode.

  6. #6
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Location
    Cleveland OH
    Posts
    17,329
    +1
    31
    Welcome to the Hulk.

    Are you sure it's fuel and not water coming out the exhaust? (water inside the waterbox will come out when revved)

    If you're saying the engine is racing without touching the throttle you have an air lean somewhere in the engine.

    I suggest doing a compression test, a leak down test, and upgrading/replacing the fuel system. Including a rebuild of the carbs.

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Question about 96 sl780 fuel delivery system...
    By jcc011185 in forum Polaris PWC Performance
    Replies: 12
    Last Post: 11-03-2011, 08:07 AM
  2. Sea doo XP limited backfiring out the exhaust
    By carms_us in forum 2-Stroke Performance
    Replies: 2
    Last Post: 04-05-2009, 06:15 PM
  3. 1996 1100 waveventure backfires out the exhaust
    By jdebold in forum Yamaha Old School Skis
    Replies: 9
    Last Post: 08-25-2008, 08:28 PM
  4. gas pouring out the exhaust
    By stxrinNLA in forum Kawasaki Open Discussion
    Replies: 4
    Last Post: 07-30-2008, 10:24 AM
  5. WTB: 96 SL780 Fuel Sender
    By barefootpolaris in forum Polaris Classifieds
    Replies: 10
    Last Post: 05-21-2008, 06:04 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
  •