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  1. #1
    GPHOTROD's Avatar
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    Apr 2006
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    Dearborn Heights, Mich
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    Still chasing RPM loss!!!!

    I have two 1300s built the same, both have always run the same rpm and the same speed. Now all of a sudden one of them lost 50-60 rpm and about 1 mph.

    Things I have already checked include.

    I have changed head gasket
    Checked the reeds - OK
    Checked and adjusted power valves - OK
    Tried a different EFI controller - no change
    Pulled pump and checked bearing - OK
    New plugs side gapped and indexed
    Checked Compression - still the same

    Anybody have any ideas?

    2003 1300 GPR 75.9 @ 7090
    Unported and Injected.
    Fercho's Package, and 3 deg key
    Head by Lowell Horning.
    Rossnemos Sonic Boom TB Mod.
    Jims FF Mod Plate & Trim Tabs.
    14/23 Solas DF Frecho Spec from Impros.
    Riva 1200 Grate.
    Last edited by GPHOTROD; 08-12-2007 at 08:10 PM.


  2. #2

    Join Date
    Nov 2005
    Location
    Brighton,mich.
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    78
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    Talking

    Any recent weight gain?
    Last edited by jy; 08-12-2007 at 06:35 PM.

  3. #3
    GPHOTROD's Avatar
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    TTT

  4. #4
    I would start by switching tachs and making sure the difference isnt in the tachs themselves...

  5. #5
    Never say never KirkF350's Avatar
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    Quote Originally Posted by rossnemo View Post
    I would start by switching tachs and making sure the difference isnt in the tachs themselves...
    That would be some sh!t if that is all it is. Probably would be a relief.

  6. #6
    That would explain the rpms but not the 1mph loss though.

  7. #7
    WATER WOODY's Avatar
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    Minden, Nevada, United States
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    Do both ski's have the pump tunnel reinforcment?

  8. #8

    Join Date
    Jan 2006
    Location
    Texas City, Texas
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    Bent impeller blade?

    Bad stator vein?

  9. #9
    GPHOTROD's Avatar
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    We share the same tach, and both boats have tunnel reinforcements. Impeller and stator look like new.
    Last edited by GPHOTROD; 08-13-2007 at 05:49 AM.

  10. #10
    GPHOTROD's Avatar
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    ttt

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