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  1. #1

    1998 gp760 carb issues

    Hey guys (and gals). I recently got a gp760 from my father. The top end was just rebuilt after sitting a while and my father said he went through the carbs to ensure all was clean.

    I checked compression and both cylinders are around 150 psi. The engine hasnt been broken in yet because I'm having some issues that i believe to be related to the carbs. The ski will only start up and run if I almost shut the gas off to keep it from loading up. I can literally see the butterflies in the carb flood with fuel if I open up the petcock while running. Seems like more in the front carb.

    On a side note, I pulled the return fuel line from the carbs and pressurized the fuel tank with my mouth. When I do this, it seems like a lot of fuel rushes into the intake right above the butterfly.

    I have been working on atvs/dirt bikes most of my life and am new to pwc's. Any pointers or advice is appreciated.


  2. #2
    This is how I run a jetski shop in the desert nmpeter's Avatar
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    read up on these carbs, get some OEM rebuild kits and go at it. Pay special attention to pop off pressure. Your carbs are flooding because the needles are leaking.

    Marine carbs are different. Study the parts diagrams, should be in your realm.

    welcome to gh.

  3. #3
    Thanks for the input and welcoming. I will start there and if I decide on keeping the ski a while, I will also invest in a manual.

  4. #4
    Great catch NMPeter. Took the carbs back apart and studied the needle valves. My dad had the pivot pins slightly angled when he tightened the holding screw down, which held the valves slightly open even when the diaphragm wasn't acting on it.

    I cleaned/inspected them and reassembled.....voila! No more flooding issue.

    Thanks!!

  5. #5
    This is how I run a jetski shop in the desert nmpeter's Avatar
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    that's a common assembly mistake. Good catch and I'm sure it felt pretty good when it ran sweet.


    oh yeah...keep your mouth off the gas tank fill. That's a quick and expensive trip to the hospital icu if you are ever unlucky enough to inhale some gasoline
    Same thing about using a cigarette lighter to check the levl of gas..just don't fall for that.
    No problem is worth hurting yourself over.

    So what's next on your list?

  6. #6
    I've never heard of cigarettes lighter to check fuel level. I've always put my stream light to the top and shake the ski loll much safer.

  7. #7
    This is how I run a jetski shop in the desert nmpeter's Avatar
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    Quote Originally Posted by red96turbols View Post
    I've never heard of cigarettes lighter to check fuel level. .
    my point...exactly.

    just don't do it!

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