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  1. #1

    Join Date
    Jun 2019

    2008 Ultra LX 1500cc won't go over 40mph

    Hi Guys, I am new to this forum, and new to this ski. It only has 60 hours on it, bought it off my friend who bought it new in 08 and obviously barely used it. It was pulling 50mph+ and now it won't go over 40 and the RPM really won't go above 5800 (is that normal?)

    Where should I start, I did a compression test it was good, Plugs looked fine. DO I have a blockage somewhere?

    Any help would be great!

    Thanks in advance

  2. #2
    Spooling's Avatar
    Join Date
    Sep 2011
    West Coast of Florida
    1. Take it for a ride with both seats off - even the rear section held on by 4-10 mm cone head nuts removed would also help - and report back if you gained your MPH back. Exhaust hose going to the H2O Box could be wasted and your "coughing" the engine with no air.

    2. Change your plugs with new. Be careful removing them and use some anti-seize on them upon re-installing.

    3. Look up inside the pump with a flashlight and see if you sucked anything up, like a plastic water bottle, rock, dead fish, or possibly an armadillo

    Good Luck !!!

  3. #3

    Join Date
    Jun 2019
    Awesome, I will try that. So my question is when I am looking ahh the pump, is that from underneath? My ski is kept at a marina on a jet dock so getting under it is hard. I would have to pull it... Thank you Spooling!

  4. #4
    I'll bet the intercooler and intake manifold that is usually gunked up with milky oil residue if unchecked for years.... needs cleaning. clean that out and you'll gain at least 10 mph. and you probably need to replace the supercharger belt and tighten the tension on it.

  5. #5
    Its an LX so its NA.

  6. #6

    Join Date
    Jun 2019
    Unfortunately its not a supercharged model. As stated plugs looked ok, but I changed them anyway yesterday and its much better. Lots of pep and now hits 50mph. I still feel like its missing a couple mph but much much better. Rips out of the hole now!

  7. #7
    It should do 2-3 mph more in chop, and about 4 more on flat water.

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