9.9 Yamaha carb lines.

Discussion in 'Bubba's Outboards' started by BailBonds, Aug 16, 2008.

  1. BailBonds

    BailBonds New Member

    Messages:
    282
    State:
    Indiana
    I cleaned up a Yamaha 9.9 hp carb. The idle jet was full of crud. Reassembled it and installed. Now it runs super rich and won't get up to normal RPM. I think I must have reversed these two lines that control the BVSV that takes the place of a choke. One of these inlets has a large hole and the other a very tiny hole. The left one has an A over it the right has a C. I did not mark as I should have. I was hanging off the back of a boat in the water. I know you're saying just reverse and try. But it carboned up and fouled the plugs really quick. It's like running with the choke on 100%. Clymers doesn't show much. Any idea on what goes where?
     

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  2. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    The carbon is most likely coming from the top of the piston or the reed valves. On the fuel lines I would have to be right there and trace them to see which is which. I would get me a can of sea foam and also a can of deep creep made by sea foam also and clean those reeds off and those pistons off before I did any more to the carbs. The deep creep you spray through the carbs and it will cut that carbon off those reed valves. On the valves it is mostly dirt and oil not carbon.
    If you didn't let those carbs soak overnight in some good cleaned then I would suggest you remove them and break them or it down and soak overnight and follow up with some fine wire and air to clean all the idle and run circuits out.
     

  3. BailBonds

    BailBonds New Member

    Messages:
    282
    State:
    Indiana
    Thanks Bubba but this is a 4 stroke no reeds. The ports I have marked are for the bi metal enrichener, I guess it replaces a choke. I'm guessing it pulls exhaust across something to heat it up and close the enrichener? I figured out the button on top comes off and you can lock the plunger in ether position. I'm gonna fight with it today. I'll post if I get lucky and figure it out.
     
  4. BailBonds

    BailBonds New Member

    Messages:
    282
    State:
    Indiana
    FYI:

    Well I did get lucky. I guess if finding out I messed up assembling it is lucky. I installed the main jet nozzle tube 180 degrees out. It has a notch cut out at the top where it sits in the venturi and I had it facing in towards the engine. I swapped it back and it runs like a pickle seeder. The two lines for the auto choke were not the problem. Thanks for trying to help.
     
  5. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Thanks for the follow up.