Yamaha Problem

Discussion in 'Bubba's Outboards' started by uapipefitter, May 30, 2008.

  1. uapipefitter

    uapipefitter New Member

    Messages:
    110
    State:
    potterville,mi
    Howdy cat'ten brothers, I have a 25 horse yamaha four stroke that ahs less than twenty hours on it and it's runnin' on like two cylinders.I went from 22 mph on my gps to 5mph and rough runnin. It was running good down the river when it bogged, picked up ran good then bogged again and has been that way since. Took plugs out, they looked good, and so did the fuel filter and pick-up tube in my tank. Any help would be great. Trent
     
  2. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Do a spark test and that will tell you if they are fireing or not. Looking good doesn't tell you much also try pumping the primmer bulb or pulling the choke on to see if it helps pick it up.
     

  3. Mike81

    Mike81 Well-Known Member

    Messages:
    4,186
    State:
    Alabama
    Not sure how those motors are set up but fuel pump maybe? or overheating??
     
  4. jtrew

    jtrew New Member

    Messages:
    4,404
    State:
    Little Rock, AR
    Choke? From looking at my 25hp Yamaha 4-stroke, and reading the manual, they don't have a choke. I guess it's computer controlled or something. Anyway, I can't find anything on the motor that looks like a choke, and can't find anything about a choke in the manual. If I'm wrong, someone please point out the choke to me! I've been trying to find a choke on it because mine is extremely hard to start when it's cold. Starts ok while it's still at operating temperature, and runs great once it warms up. But if you let it set till it cools down, it's hard to start back up again. I was wondering if a little starting spray would help. Do you think there would be any danger of damaging the engine by using the starting spray?

    Trent, when your engine starts bogging down, look very carefully at the red engine light on your engine. Among other things, that checks oil pressure. I'm sure you check your oil level every time before you use it, but I had the computer on mine say that the oil was low, or it had low oil pressure from when it was new. Finally, the third time I took it to the dealer, Yamaha said to replace the computer, and that fixed that problem. But it's been hard to start ever since.
     
  5. cantstopgrandma

    cantstopgrandma New Member

    Messages:
    955
    State:
    MD
    When i bought my 25hp 2stroke yamaha last summer, i listened to the salesperson tell a guy getting a 20hp 4 strk about what he should do. She said the 4 strokes dont like water in the fuel, and even a small amount causes problems. She recommended a fuel water separator to him. She went on to explain that plastic gas tanks make water, going on to say that you can stick a new, empty plastic ziplock baggy in the sun and it will have water in it when you come back. Nowadays we also hafta worry about alcohol in the fuel, which likes to collect moisture. These may not be your problem, but its something else to check.
     
  6. jtrew

    jtrew New Member

    Messages:
    4,404
    State:
    Little Rock, AR
    I don't have any problem once the motor is running good, but maybe there's just enough water to cause hard starting. I'll have to check into getting one of those things. I had to get one on a big 20' deep V I used on the Pacific where I was burying the front deep enough in the big waves to suck water into the gas tank breather opening.
     
  7. olefin

    olefin New Member

    Messages:
    3,908
    State:
    Texas
    I have a 60 HP Merc 2 stroke EFI. Now 4 years old, never a problem with starting or running. Also plastic fuel tank. Starting is what I like best with the EFI 4 stroke. Hot or cold just bump the starter. Same after 6 months winter storage.
    My 15 year old 85 Yamaha 2 stroke has been slow to start when cold from day one. It starts at a touch of the starter when hot.