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  1. #1

    SLT780 Running hot?

    Hey all, long time reader, first time poster. Been working with my polaris for over a year and now I'm switching hulls this year to another that I painted during winter. Anyways, my problem I have is the exhaust rubber fittings that connect the exhaust manifold to the muffler then from there to the pump area, they are bubbling from the inside like its being over heated. I've had to change out one piece before cause it really bubble up and clogged the exhaust until it blew out before I lost RPM. I thought it was running too rich until I discovered the front piston threw a chunk into the spark plug electrode so I'm guessing that indicates a lean issue (I didn't notice the piston issue, it still ran fine). . . I'm rebuilding the engine again but can't figure out what that exhaust issue is, any info or same probs?


  2. #2
    urugol's Avatar
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    Welcome to the hulk.

    Sounds like you need to check the exhaust pipe orifice, if that gets blocked you can burn up your rubber hose between the water box and exhaust.

    Here's a good thread to help you: http://www.greenhulk.net/forums/showthread.php?t=149069

  3. #3
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Quote Originally Posted by Wolf_Rider View Post
    Hey all, long time reader, first time poster. Been working with my polaris for over a year and now I'm switching hulls this year to another that I painted during winter. Anyways, my problem I have is the exhaust rubber fittings that connect the exhaust manifold to the muffler then from there to the pump area, they are bubbling from the inside like its being over heated. I've had to change out one piece before cause it really bubble up and clogged the exhaust until it blew out before I lost RPM. I thought it was running too rich until I discovered the front piston threw a chunk into the spark plug electrode so I'm guessing that indicates a lean issue (I didn't notice the piston issue, it still ran fine). . . I'm rebuilding the engine again but can't figure out what that exhaust issue is, any info or same probs?
    Welcome to the Hulk.

    Unfortunately, you are not alone on this one. The 780 uses a 1mm orifice for keeping the rubber hoses cool in the exhaust system. Water is injected into the exh stream to keep these parts cool, and prevent blistering like you're experiencing.

    Check the fitting as Urugol suggested, but I'm going to guess it's clear. Polarisnut#1 and myself have had the same issue and haven't put our finger on the exact issue yet. He however went with the 750's 2.3mm orifice and has seemed to solved his problem.

    http://www.greenhulk.net/forums/show...ighlight=burnt

  4. #4
    Awesome, why that didn't dawn on me I don't know, will check into that, thanks all!

  5. #5
    urugol's Avatar
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    How about running a 3 ply silicone hose in place of the rubber? Those things are rated for extreme temps if all else fails.....

  6. #6
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    You can obviously just drill out yours bigger too. That way you don't have to get another one.

    Just do not drill bigger than 2.3mm as this will affect your pipe's "tune"

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