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Fuel in the crankcase..

  1. #1
    Lifer Gixxer's Avatar
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    Fuel in the crankcase..

    Iím my quest to get a third bike, and it be a crotch rocket, I found one Iím really interested in but it may be too much of a project for me.

    Along with other issues, it has fuel in the crankcase?

    Does that mean the piston rings are toast?

    Does that mean a top end rebuild?

    What would that cost on an inline four?

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    Your park avenue leads to..

  2. #2

    Re: Fuel in the crankcase..

    Injected or carbs? fuel is still flowing, floats sticking open if carbureted or leaky injectors.

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    Last edited by MUZ720; 07-11-22 at 04:51 PM.

  3. #3
    Lifer Gixxer's Avatar
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    Re: Fuel in the crankcase..

    Carbs, which need cleaning.

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    Your park avenue leads to..

  4. #4
    Being A Dick PurplePackage's Avatar
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    Re: Fuel in the crankcase..

    How do you know it's fuel, and when was the last time someone tried to start it? Fuel can leak down into the lower engine if it's cranking but not starting and someone sits on the start button, sucking fuel down into the chamber and letting it soak down into the crankcase.

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  5. #5

    Re: Fuel in the crankcase..

    clean carbs make sure float level settings are correct. drain oil.

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  6. #6
    Lifer
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    Re: Fuel in the crankcase..

    What are you looking at?

    Sticking floats can easily dump fuel into the crankcase. Could be level too or several other things.

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  7. #7
    Lifer zxme's Avatar
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    Re: Fuel in the crankcase..

    Sticky float also could be a faulty petcock

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  8. #8
    Member lrrs398's Avatar
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    Re: Fuel in the crankcase..

    I was able to get a couple 2012 Ninja 250's that were used for the MSF class very cheap. What happened to one of them is that the fuel petcock let the fuel flow (instead of only when the engine was running) and the crankcase became full of fuel. I bought a used petcock for $40 from eBay, replaced the plugs and drained / refilled the oil and no more issue.

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  9. #9
    Lifer Kurlon's Avatar
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    Re: Fuel in the crankcase..

    If the bike is just sitting and not being jostled around, the floats should absolutely prevent the crankcases from filling. The petcock is just an additional safety. As long as the bike wasn't run much with heavily thinned out oil there shouldn't be any damage to worry about.

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  10. #10
    Being A Dick PurplePackage's Avatar
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    Re: Fuel in the crankcase..

    Yes, clear the carbs and fuel lines, then drain the oil and refill with cheap motor oil to flush it. Put a mile on the bike, enough to warm it up, then get a new filter and do a 2nd oil change with full synthetic.

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  11. #11
    Angry Gumball RandyO's Avatar
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    Re: Fuel in the crankcase..

    Quote Originally Posted by zxme View Post
    Sticky float also could be a faulty petcock
    th

    sometimes both fail, I checked the oil in my XV920R once, and drained 7 quarts from a 3quart capacity crankcase

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    RandyO
    IBA#9560
    A man with a gun is a citizen
    A man without a gun is a subject LETS GO BRANDON

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