Yamaha 60 2 stroke fuel starvation

Discussion in 'Outboard Maintenance' started by Bridgette1, Dec 3, 2013.

  1. Bridgette1

    Bridgette1 I Love microskiff.com!

    69
    0
    81
    My motor fires right up and runs perfect but when I run it hard around 5,000rpm or higher it sometimes Boggs down due to fuel starvation. If I squeeze the primer bulb while it is bogging it comes right back to full power. At first I figured it was likely a bad primer bulb but it is not collapsed when this happens. It is soft (not rock hard) but not collapsed. Motor runs perfect at any and all other rpm's. It seems to be an intermittent problem it does not do it every time I run it hard. Any ideas?
     
  2. Creek Runner

    Creek Runner Well-Known Member

    1,544
    23
    643
    Primer bulb, anti siphon valve, fuel pump.
     

  3. swaddict

    swaddict Thread Killer

    693
    43
    403
    what Creek said, he helped me with the same problem and he knows his stuff, unfortunately you'll have to replace one at a time until your issue is resolved
     
  4. cutrunner

    cutrunner Cert. Yamaha technician

    Might I add, if you replace your primer bulb please replace it with a yamaha bulb. No moeller etc..
     
  5. Bridgette1

    Bridgette1 I Love microskiff.com!

    69
    0
    81
    Thanks guys, I guess I will start with the primer bulb and go from there.
     
  6. danville_marine

    danville_marine I Love microskiff.com!

    95
    0
    81
    ive had problems with inside of fuel hose coming apart
    clogging the fittings
     
  7. Bridgette1

    Bridgette1 I Love microskiff.com!

    69
    0
    81

    I am going to replace the entire fuel line from the tank to the motor with the new primer bulb. Hopefully that resolves it.
     
  8. Gatordebaitor

    Gatordebaitor I Love microskiff.com!

    73
    1
    83
    That tank is notorious for a bad anti-siphon valve - might as well do that to while you are at it.
     
  9. Bridgette1

    Bridgette1 I Love microskiff.com!

    69
    0
    81
    Will do.
     
  10. Bridgette1

    Bridgette1 I Love microskiff.com!

    69
    0
    81
    Thanks again for all the suggestions. I replaced the primer bulb, no better. Replaced the fuel line, no better. I removed the anti-siphon valve and the problem is solved. Now I wish this wind would settle down so I can go fishing!
     
  11. restlesswoodie

    restlesswoodie I Love microskiff.com!

    45
    0
    331
    I think I am having the same problem as you. I have a 99 Yamaha 60 and the motor runs perfect at every speed but wide open. I thought it may be gas related or clogged carbs. Once it happens when I run full throttle it bogs down and continues to do so until I shut the motor off and let it sit for a minute. Is the anti-siphon valve in the tank itself and can I remove it completely or replace?

    Boat is a 99 Maverick 16 tunnel
     
  12. Creek Runner

    Creek Runner Well-Known Member

    1,544
    23
    643
    Yes the anti-siphon valve is in the tank, it's located in the fuel pick up. Pull the pick up out and the valve will be located in it. It's a check valve.

    I would advise the order in my 1st post.
     
  13. Bridgette1

    Bridgette1 I Love microskiff.com!

    69
    0
    81
    The barbed fitting on the top of the tank that the fuel hose leading to the motor is connected to.  I removed mine completely but that is your call. Do a little research on what it does and why it is installed before you decide. You might want to replace it rather than remove it.
     
  14. Creek Runner

    Creek Runner Well-Known Member

    1,544
    23
    643
    The A/S valve purpose is to cut off fuel flow in case of a leak or fire where the fuel line could dip below the top of the tank.

    I haven't checked regs in a while, but when we were build drag boats if the fuel line never dipped below the top of the tank uscg regs did not require one. Again it's been a while so check the regs if your concerned.