50hp Mercury

Discussion in 'Bubba's Outboards' started by bigfish, Mar 1, 2006.

  1. bigfish

    bigfish New Member

    Messages:
    432
    State:
    Dunbar WV.
    hey bobpaul and bubbakat a friend of mine has a 50 hp merc. setting on the boat with muffs on it will idle and rev up just fine. but as soon as you get it on the water and try to throtle it it bogs down. now not sure year of the motor. but i think its a pretty old one. the distributer turns when you throttle it. it has 2 carbs. i looked for modle # but it wasnt on the shaft like its supposed to be. all i could find to identify it was 50 four on the cowl. he says when on the water sometimes if he turns the wheel left and right while going down the river it will straighten up. im not sure thats why im asking you all. but it sounds to me by making the boat rock like that helping it some could be one or both floats. all thoughts would be appr.
     
  2. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    He can adjust the carbs to let it accelerate when throttled. What I would do is soak and rebuild the carbs. Those things are real sensitive about carb adjustments. I will look in my book and see if I can find the adjusting procedure.

    If you can get a picture of the motor and one of the carbs and that will help me identify it for him and get all the particulars he needs.
     

  3. Bobpaul

    Bobpaul New Member

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    3,039
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    And let him know, not to be revving it on the muffs. No back pressure will allow it to over rev and no way to stop it immediately.

    After the carbs, do the rest of the fuel system. New gas, clean filter, flush out lines before connecting them back up to the carbs.
     
  4. dinkbuster1

    dinkbuster1 New Member

    Messages:
    2,272
    State:
    Ohio
    my 25hp johnson developed a similar problem last year. it would bogg down on acceleration and would stay bogged for about 30-40 seconds and would then take off. had a shop look at it after i gave up on trying to adjust everything and tured out there was a peice in the intake that was busted causing way too much gas to be dumped into the motor. it looks like a flower with a 8 petals and one of them was broke off. cost me $250 to have it fixed but it runs great now.
     
  5. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Dink those are called reed valves and those seldom go bad.

    Thanks Robert for covering my old forgetful buttttt on that one.:) :)

    man i am getting forgetful.:p

    Pay real close attention what bobpaul said about reviving on muffs. That is what is called a runaway. When it does that about the only way to shut it down fast enough is to stuff the carbs with rags and by the time you do that it has already flew apart.
     
  6. bigfish

    bigfish New Member

    Messages:
    432
    State:
    Dunbar WV.
    thanks for the info. ill try to get serial # off freeze plug pluss i will take a picture. i did forget to mention i did a compression test, all 4 cylinders had 120# pressure. i kinda thought it had to do with the carbs. will be looking at it again sunday. will keep you all posted. thanks on info about reving up with muffs. will tell him we need to get a barrel. you guys are a great help.:) ps that was a faster reply than mcdonals.
     
  7. bigfish

    bigfish New Member

    Messages:
    432
    State:
    Dunbar WV.
    well first my friend says this 50hp is a 1969 i found a serial # on it 2011541. i havent convinced him yet that its in one or both of his carbs. so we took it out on the water today. the motor will idle fine, but when you give it full thottle it only goes about one mile an hour, with a missing sound. i tried pumping the primer bulb while it was running to see if maybe the fuel pump was working and it didnt make any differance. but i also found by pumping the bulb it would cause fuel to come out the carbs. so do i realy have a fuel problem or could it be a distributor cap or point problem.
     
  8. Bobpaul

    Bobpaul New Member

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    3,039
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    Sounds like it's flooding. You should never get fuel out of the carbs by pumping the primer bulb. It shows that the needle's not seating and too much fuel is flowing.

    Get them cleaned and pay attention to where they're adjusted now to put the adjustment back where it is.
     
  9. bigfish

    bigfish New Member

    Messages:
    432
    State:
    Dunbar WV.
    thanks bobpaul going to order carb kits tomorow, if i can find them for that old a motor. be about 2 weeks before i get parts. i will post as soon as i can.
     
  10. Bubbakat

    Bubbakat New Member

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    4,532
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    McMinnvill
    Jim if you have any trouble finding those kits just let me know and I will send you a link of a guy that has them.
    Be sure to soak those things good and blow out all the little oriffces with compressed air.
    The little springs that are in the floats are real critical so don't attempt to stretch them any.
    I will post the proper procedure tomorrow on the setting for the carbs.
    You will have to do the final setting with it in gear and in the water under pressure.
    If your manuel doesn't have the good eploded views of the carb let me know I have some that I will e-mail you that I took a long time ago.
    No copy right infringments here.:)
    Those things are trickey but are good if properly stored at winter time.
     
  11. bigfish

    bigfish New Member

    Messages:
    432
    State:
    Dunbar WV.
    thanks bubbakat, i might need the eploded veiw. will no more about whats going on for parts today. thank for all the quick help.
     
  12. bigfish

    bigfish New Member

    Messages:
    432
    State:
    Dunbar WV.
    well i guess this guy dosent believe that it is the carbs. i found the kits, they are in stock. all he said when i called is i will call you if i decide to get the kits. thanks for trying to help me help him.
     
  13. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Well fish at least you tried to help him.
    Just tell him if one of those carbs is flooding look in the near future for a piston to destroy its self.
     
  14. bigfish

    bigfish New Member

    Messages:
    432
    State:
    Dunbar WV.
    yea i know, i guess he will just putter around the river at 1mph cause thats all it would do while i was in it. like you said we tried.
     
  15. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    Does he invite you along so he'll have help rowing that thing back to the dock?

    Stay out of that boat unless you really believe you owe him some serious labor.

    You tried, that's all a friend can do. Good job in that.