Results 1 to 5 of 5
  1. #1

    Question Sl 900 hits high rpms only sometimes?

    I just updated the ignition, had the carbs rebuilt, and ski starts and runs awesome, except for this little issue. It comes out of the hole and planes easily, but gets stuck at around 45 mph, and then all the sudden the motor really kicks in and it shoots to about 60mph like someone hit a nitrous button. I can get it to do it at slow speeds if I go in a donut for 20 seconds or so, but it will never go to the high rpms at takeoff. It doesnt stumble or hesitate, and the mdf just stopped working so I unplugged it. It has to be jumping up 1000 rpms or so when the engine kicks in, once I'm moving along. Is this just how they drive, or should it reach those high rpms at takeoff or whenever I give it full throttle?

  2. #2
    Click avatar for tech links/info, donation request K447's Avatar
    Join Date
    Jul 2007
    near Toronto, Canada
    What settings are the carb screws at?

    Was the fuel system also cleaned out with new fuel hoses and filter?

    Correct spark plugs installed?

  3. #3
    Ive recently noticed this exact same phenomena on my 96 SL900 that is converted to a 1200...when first going along it will only pull 6100rpm, then all of a sudden it will pick up to 6900-7000rpm (I am a bit under-propped for the 1200). It will continue to rip at this higher RPM until I shut the machine off for a while. I have recently cleaned and inspected the carbs, and wash on my center and pto cylinders looks good, but very front cylinder looks rich...I was chalking this up to old plugs, but maybe there is something else going on. My first step is new plugs properly gapped and cut 1/4 of the plug wire back and re-seat the plug caps.

    Anyone else had this happen?

  4. #4
    Exactly, I cut back the wires already, and put new plugs in it. All the fuel lines have been replaced also. I don't know about the carb screw because a mechanic rebuilt the carb for me. My prop looks good, but the black fins in front of it do have a couple of chipped spots on it. I'm at a loss. If it would come out of the hole at those higher rpms it would be a beast! Could it be something with the ignition update, like a wire in the wrong spot in the electrical box, or since it starts and runs all that stuff is right?

  5. #5
    There are not any high speed jets on the sl900, so Im at a loss. Could the jet pump be needing to get up and out of the water to reach higher rpms since there is some chips in the pump stator?

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. XL1200 cavitation at high RPMs
    By jamie327 in forum Yamaha PWC Performance (2-stroke)
    Replies: 13
    Last Post: 03-19-2009, 07:17 AM
  2. high RPMS
    By MONKEY in forum 4-Tec Performance
    Replies: 3
    Last Post: 09-05-2007, 11:53 AM
  3. High RPMs At Idle
    By JFizzleJR in forum 4-Tec Performance
    Replies: 28
    Last Post: 07-09-2007, 08:50 AM
  4. 1300 Still has High RPMs
    By Purple Haze in forum Yamaha PWC Performance (2-stroke)
    Replies: 4
    Last Post: 10-01-2006, 08:04 AM
  5. 900 bucks for 3 year extended warrantee is it too high???
    By GSXER2 in forum Sea Doo Open Discussion
    Replies: 12
    Last Post: 06-13-2005, 09:57 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