Thread: No rpm no lift

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  1. #1
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    Mar 2020
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    No rpm no lift

    I had a little boat trouble back in June. Rectifier flamed out. Just finally got her back from shop. New-rectifier, stator, power pack, all 3 coils, new plugs and new throttle body’s on carbs. Took her out this weekend and she’s not running like it should. She is a 97 cobra 188dc with 150 fast strike. 24 raker 6” plate. Best I could get was 48mph. No bow lift and only turning 5000 rpm, barely. The motor has 115-120 psi compression in all cylinders. I know it’s not going to be a speed demon but it used to touch 59-60 with beat up raker prop. I bought a new prop just before the fire that’s on it now. I think I should be spinning more rpms, 55-5600. Any suggestions?

  2. Member
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    Mar 2015
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    #2
    What pitch was your beat up Raker? 24 sounds like it would be too much for that boat/motor combo.

  3. Member
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    #3
    It’s a 24 as well. I presume it was the original prop I bought the boat from my wife’s uncle about 5 yr ago and he bought it new. I’ve wondered if I need to drop to a 22 maybe.

  4. Member
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    #4
    If it was running those speeds before, I'd be having the shop that did the work look at it to make sure the throttle is opening all the way up.

  5. Member
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    #5
    Yea well that won’t happen. Kind of a bad experience. The ONLY reason it was there in the first place was for insurance. I think i might need to check the link/sync. The throttle body’s were replaced because the fire extinguisher powder got in them and seized the shafts up. They wouldn’t move at all.

  6. Member
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    #6
    Quote Originally Posted by Cobra96188 View Post
    Yea well that won’t happen. Kind of a bad experience. The ONLY reason it was there in the first place was for insurance. I think i might need to check the link/sync. The throttle body’s were replaced because the fire extinguisher powder got in them and seized the shafts up. They wouldn’t move at all.
    It does not matter why you had that particular shop work on the motor, but since they were paid for doing the work, you should hold them accountable for doing it correctly.

  7. Member
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    Aug 2009
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    DeSoto, MO
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    97
    #7
    was the beat up raker an original raker and the new one a raker 2 by chance? i had the same issue with my old bass cat and evinrude 200 looper the new rakers are a lot stiffer than the originals and will not turn the same
    2000 Cobra 201d
    2000 opti 225

    "if your gonna be dumb you gotta be tough"