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  1. #1

    255hp SCed engine question

    Hi, I posted this in the boat section, but since there's more of you guys in the pwc section and my boat has the same engine and its practically a pwc I thought someone here might be alble to help me or knows something about my problem. thanks for your time.

    Im new to all this, I own a 2010 255hp speedster 150, its new with 20 hours. I'm having a problem hope you can help me. the dealer hasnt been able to give me an answer…

    Ok, this is whats happening, after a few minutes of cruising or skiing at relative low speed (up to 30mph) when I try to accelerate the boat looses power, then it comes in like in pulsations, so it pulls and drops like wo wo woo wooo wooo till it picks up speed, once it gets up to speed it seems normal, if I run at high speed for a few seconds then I can slow down and accelerate hard again like nothing ever happened, and if Im running it hard all day it acts normal and pulls well all day.

    But as soon as I start cruising or going slow for a minute or so, then it has trouble accelerating again, the dealer tells me it cant be the supercharger because then it wouldn't pick up speed again, they tell me that if the sc is gone power doesn't pick up again and it doesn't act like that, and that it must be the gas pump or something electrical. so can the supercharger slip like that?

    to be honest I really don't feel its the gas pump, but I have no experience, I really hope someone can help me.. is this something familiar to this boats? has anybody heard of something like this? the dealer told me they have never heard of something similar, their clueless and they haven't had the time to come over and check it… HELP PLEASE! thanks again!!and sorry for posting a boat and the pwc section


  2. #2
    b_dolla44's Avatar
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    I've never heard of anything like this...But, I can tell you this. If you RPMS are gone past 7600 its NOT you SuperCharger...I'm thinking more like a Drive by wire issue...(not sure if the 10 boats are even using Drive by wire)
    But, thats my best guess....

  3. #3

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    Worn wear ring and hitting the limiter? Look in the pump tunnel and see if your wear ring has groves in it. the wear ring is what the impellar fits in.

    When you take off does the engine rev and the boat move slowly and once it builds up some speed take off. If this is the case you need a new wear ring in the pump.

  4. #4
    Mod less, ride more! troyheb's Avatar
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    At aprox what rpm are you cruising before this happens?

  5. #5
    Quote Originally Posted by Bama View Post
    Worn wear ring and hitting the limiter? Look in the pump tunnel and see if your wear ring has groves in it. the wear ring is what the impellar fits in.

    When you take off does the engine rev and the boat move slowly and once it builds up some speed take off. If this is the case you need a new wear ring in the pump.
    its not hitting the limier... its the engine that is pulsating as if i was moving the accelerator back and forth, so the revs are going up and down.

    When its running well it runs around 8000rpm, but after driving it slow for some minutes and when the problem is present its pulsating or jerking up to like 5000rpm aprox, after that it pulls normal, then if I run it over 7000rmp for a few minutes it acts normal, then I can drive at any rpm and the boat pulls well, as long as I don't sustain speeds under 30mph for a few minutes, because then I lose power again and have the same problem accelerating

  6. #6
    Quote Originally Posted by troyheb View Post
    At aprox what rpm are you cruising before this happens?
    between 20 to 30mph, not sure what rpm is that, around 3k to 4k i guess... the boat is new so please excuse my ignorance about all this, its my first boat

  7. #7

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    Changed the spark plugs recently? Had similar symptoms earlier in the season, all sorts of misfires in the mid-range. Ran great at WOT. Changed the plugs and was good to go.

  8. #8
    Moderator beerdart's Avatar
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    1+ change your plugs.
    Quote Originally Posted by xylene View Post
    Changed the spark plugs recently? Had similar symptoms earlier in the season, all sorts of misfires in the mid-range. Ran great at WOT. Changed the plugs and was good to go.

  9. #9
    Mod less, ride more! troyheb's Avatar
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    Quote Originally Posted by G.R.B View Post
    between 20 to 30mph, not sure what rpm is that, around 3k to 4k i guess... the boat is new so please excuse my ignorance about all this, its my first boat
    I would say that if it was doing it around 6000 rpm then the Sc was slipping, but it sounds like something else.

    Quote Originally Posted by xylene View Post
    Changed the spark plugs recently? Had similar symptoms earlier in the season, all sorts of misfires in the mid-range. Ran great at WOT. Changed the plugs and was good to go.
    +1
    This is a good place to start.

  10. #10
    I'll change the plugs and see what happens, but if it was a spark plug do you all think it would still explain why after running over 7000rpm for a couple of minutes it runs perfectly normal at ANY rpm?

    I could think that a bad plug would be a constant problem yet it goes away in certain circumstances, it feels as if it goes away when the engine is really wormed up after some some moments at high rpm, and maybe after going slow for a few minutes it cools enough to start with the problem, i don't know if it would actually work like that or backwards or if temp has anything to do with the problem… Im just guessing

    I'll see to the plugs as soon as I can and let you know what happens. I really appreciate all of you taking the time to help me out

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