25hp merc 2strk backfiring

Discussion in 'Outboard Maintenance' started by bw510, Nov 20, 2013.

  1. bw510

    bw510 I Love microskiff.com!

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    Is it normal as I'm coming off plane and getting off throttle to backfire slightly?
    The motor runs smooth at wide open and idle but popping a bit when letting off
    I Was planning on taking it on a trip and didn't want any issues..

    It's a new motor to me so im trying to get use to all it quirks

    Thanks
     
  2. Dillusion

    Dillusion devilray snob

    Not normal. Sounds like 'lean sneeze'.

    your carb is clogged up, probbaly a low speed jet.

    Clean it out and re-adjust your carb and idle speed to the proper RPM (850 I believe).

    Idle speed screw w spring on side of carb, as well as the air/fuel mixture screw above the carb throat should both be 1.5 turns out from lightly seated +- 1/8 of a turn.
     

  3. bw510

    bw510 I Love microskiff.com!

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    Thank you sir!
     
  4. cutrunner

    cutrunner Cert. Yamaha technician

    Backfire on decel sounds like it might need reeds
     
  5. bw510

    bw510 I Love microskiff.com!

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    I'll check the carb then the reeds.would it be normal to need them on a low hour 2005?
     
  6. cutrunner

    cutrunner Cert. Yamaha technician

    Not exactly but a 2005 is still 8 years old. I don't know if they use fiberglass or stainless steel reeds either.
    But anything can happpen. Many a time have brand new parts nit worked
     
  7. Dillusion

    Dillusion devilray snob

    2005 is SS reeds. One on each side of the triangle reed block.
     
  8. yellowfever

    yellowfever I Love microskiff.com!

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    the stock reed is steal. ur problem is not reeds. I have worked on many 18-25 mercs and never found a burnt or broken reed in those motor. but reeds will help smoother ideal,faster acceleration,better top speed. try them! www.chriscarsonmarine.com