Guesstimating pitch on a 30hp Yammi

Discussion in 'Prop Shop' started by SWFL_Gheenoe, Dec 29, 2017.

  1. RunningOnEmpty

    RunningOnEmpty I Love microskiff.com!

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    Show me a picture of the spark plugs before wasting money on a prop.
     
  2. SWFL_Gheenoe

    SWFL_Gheenoe Active Member

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    Top is top cylinder, middle is middle cylinder and bottom is... you guessed it :p

    Im not a plug genius, so please tell me that this is my problem!
     

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  3. RunningOnEmpty

    RunningOnEmpty I Love microskiff.com!

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    My old 30hp plugs always had a light brown color like your bottom plug. All 3 always looked the same unless I had a dirty carb. Are those plugs fairly new?
     
  4. SWFL_Gheenoe

    SWFL_Gheenoe Active Member

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    Yep. about 10 hours on them.
    Im thinking of asking my local shop about the possibility of tuning the carbs. Could that be the difference?
     
  5. RunningOnEmpty

    RunningOnEmpty I Love microskiff.com!

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    The low speed mix screws could be out? Did you check the fuel pump and clean the carbs properly?
     
  6. SWFL_Gheenoe

    SWFL_Gheenoe Active Member

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    No clue where the low speed mix screws would be - but I’ll ask. And yes, cleaned the pump w/new gaskets and carbs cleaned
     
  7. RunningOnEmpty

    RunningOnEmpty I Love microskiff.com!

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    Did you remove the high and low speed jets along with the orifice tubes? Sometimes everything needs a soaking in carb cleaner to get them clean or a ultra sonic cleaner. The adjustment screws are on the top left side of each carb. It's a small flat head screw with a spring behind it. I would mark them and then gently run them in until they stop. Do not force them in! Count the turns as you go. I think a good starting point is 1 1/2 to 1 3/4 turns out from lightly seated. Those screws should've been removed during the cleaning process.
     
  8. RunningOnEmpty

    RunningOnEmpty I Love microskiff.com!

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    This isn't a good example because it's a different motor, but it's helpful.
     
    Last edited: Feb 7, 2018
  9. Smackdaddy53

    Smackdaddy53 Zephyr Cove is on FIRE!

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    I would have gone to a prop guy by now. I have no patience for things limiting my fishing time.
     
  10. SWFL_Gheenoe

    SWFL_Gheenoe Active Member

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    Ahaha this was by no means limiting my fishing time - the boat scoots along just fine with the current prop, I was just trying to figure out where the other RPMs went.

    Im currently limited right now by my truck anyways... Broke down yesterday, with symptoms of either a bad crank position sensor or a clogged IPR screen.... yay ._.
     
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  11. Smackdaddy53

    Smackdaddy53 Zephyr Cove is on FIRE!

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    Good luck getting that CKP sensor out. I’m about to replace mine too. Guessing you have a 6.0...
     
  12. SWFL_Gheenoe

    SWFL_Gheenoe Active Member

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    Got a call from the shop today... Leaky STC fitting ._.
    I Love love LOVE my truck, but it left me stranded for the first time yesterday, so were gonna have a talk when it gets back from getting fixed :p
     
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