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Altitude Adjustment Question

Discussion in 'The Outboard Church' started by shueman, Jun 19, 2011.

  1. shueman

    shueman #141

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    I'm running an older 90hp Yamaha carb'd 2-stroke. We're headed to the Sierras next month for a few days and the lake is at 5500'.

    I've been up around 4000' with no issues. Can't find my service manual so I thought I ask the o/b guru's on RDP.:thumbsup

    Anything I can adjust to add air to the mixture (if needed)...?
     
  2. SloWhacker

    SloWhacker Banned

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    I ran my carbed 200 Blk Max at Huntington (7000 ft) with no adjustments for yrs.Ran awesome.I just propped down when skiing.You will be fine.Should any issues arise,see Sheldon@ Sierrra Marina.Excellent mechanic.Youre gonna have a great time.I cant remember when Shaver was this full.:)
     
  3. rivermobster

    rivermobster Club Banned

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    Any pics?? I've never been there, but the pics I've seen have been awesome.
     
  4. SloWhacker

    SloWhacker Banned

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    It sux up here.....:)

    I have more i will post after i find them........:grumble:



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  5. shueman

    shueman #141

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    Thanks...:thumbsup Despite it's age, the motor is like new inside...perfect for puttin' around looking for fish...;) Leaving this coming Sunday...
     
  6. Luv2gofast

    Luv2gofast Well-Known Member

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    Ski at Huntingon:bowdown: I did it once...tooooo cold for me!
     
  7. Outnumbered

    Outnumbered Don't tax me bro!

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    is it oil injected or premix?
     
  8. SloWhacker

    SloWhacker Banned

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    Why would that make a diff???
     
  9. Faceaz

    Faceaz Well-Known Member

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    It would. Injected engines won't load up as much at idle. As an example, some of the old OMC VRO set-ups lean out to nearly 100:1 with no load @ idle, then go to 50:1 when the engine is put under load. Premixing @ a constant 50:1 will tend to load it up a bit more because the engine can't cut back the oil with reduced load.

    I never liked the VRO because it's mixing before it gets to the float bowls, so if you get on the gas from idle, there's a little lag time before the engine will adjust to 50:1. Then again, I just grenaded our motor a few weeks ago, so WTF do I know.. LOL...
     
  10. SloWhacker

    SloWhacker Banned

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    I have also ran a pre mix 200 up here with no adjustments and no issues.:cool: Sorry bout your motor.:(
     
  11. BajaMike

    BajaMike Well-Known Member

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    If the motor has an air filter, make sure its clean or put in a new one. Also, I would buy a lower pitched, aluminum prop just in case you need to prop down.
     
  12. shueman

    shueman #141

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    Thanks for the input y'all...:thumbsup Just had to postpone the trip due to some issues with the wife's work...:( Rental company was very understanding and will honor our reservations in Sept...:cool:
     
  13. shueman

    shueman #141

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    Injected...and has been perfect, so far...;)
     

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