1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

Discussion in 'Bubba's Outboards' started by achilles555, May 7, 2009.

  1. achilles555

    achilles555 New Member

    Messages:
    21
    State:
    MO
    I just bought a 1987 Bass Tracker about a week ago. The motor is a Mercury Classic Fifty 45 HP, with serial number OB161091. The motor has sat for 2 years without being started, so I went through and did the basics. I greased everything with a good mercury grease, replaced the water impeller and gaskets, replaced the starter (it was corroded and bad), checked compression on all 4 cylinders (120 each cylinder), and tested for spark. Everything looks great. I took the boat out to the ramp for the first time today, and fired her up. Started on the first turn of the key and it sounded great. Purred like a kitten. I was pretty excited. Things went downhill from there.

    After it ran for a little bit (30 seconds?), it sounded like it was flooding out, then finally died. I tried starting it several times, and noticed a LOT of gas on the water. Turned it over a couple more times...and poof! I had a fire on my hands. After getting that put out, and checking for any damage (which there was none, thankfully) I took the cowling off, and watched the carbs. A thick stream of gas was squirting through the bottom carb every time i turned the engine over, and also when I pumped the bulb. I tapped on the float bowl with the end of a screwdriver, and got nothing.

    Seems to me like i've got a stuck float...maybe both of them, and may need a carb rebuild. I really don't know at this point. The carbs are something I really don't want to mess with. My Seloc manual sucks for this motor, and it's hard to follow. The motor is in excellent condition...I just don't feel comfortable removing the carbs.

    I tried getting to the bowl to see if I couldn't just remove it and clean it out, but with this motor, it's nearly impossible to get to. I just don't know what to do next.

    Does anyone out there have any suggestions for me to fix this thing? Is there anything I can try that might get the float to break free without damaging anything? I think if I could get the float free, I could run a good carb cleanser through the motor in a tank of gas. Any suggestions/help would be much appreciated. AC.

    Bubbakat, you've been a huge help to me in the past...what would you recommend doing?
     
  2. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    There is no quick fix for carbs that have sat unused for that long. A good rebuild is what I would do. Now you can take some sea foam and a good syringe and take the line loose at the pump and inject sea foam into the carb and let it set. That might cure the float temperately. But you will be plagued with a rich running cylinder with out a rebuild and it will destroy the piston latter on down the water.
    I hope you did use new gas and after 2 years all the rubber hoses in the fuel system needs replaceing also.
     

  3. seahaggy

    seahaggy New Member

    Messages:
    219
    State:
    kentucky
    Bubbacat is right time to rebuild the carbs.With gas flowing out like that you may have a stuck needle valve and float.Carb kits are cheap or at least mine was and i did the job myself with the help of some friends on here and the engine manual.
     
  4. achilles555

    achilles555 New Member

    Messages:
    21
    State:
    MO
    hey gentleman. thanks for the reply. after taking a closer look at the carbs and floats this morning. looks like the carbs are going to be really difficult to get to on this little 45 HP Merc. this may be one of Mercury's workhorses, but the design and placement of the carbs certainly won't win any "convenience" awards. I think I'm going to let a mechanic do a thorough check and rebuild of my carbs instead of tackling this one myself. For both my sanity...and the health of my marriage.

    I found a mechanic that is going to rebuild the carbs for me for between $200 and $250 parts and labor. That seems like a pretty fair price to me, although it is not a marina or a certified tech. Does that seem like a pretty fair estimate to anyone else out there?
     
  5. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    That is about what a certified tech would charge. Ask him how he goes about setting the carbs and get back to me on that one.
     
  6. coach

    coach New Member

    Messages:
    1,564
    State:
    Greenville , Ms
    pay attention achilles !!!!!!!!!!!!!!!!!!!!! please..........
     
  7. achilles555

    achilles555 New Member

    Messages:
    21
    State:
    MO
    Thanks Bubbakat. I will ask him and get back to you this evening. Getting ready to take the boat over to the guy. I'll feel him out and report back. Thanks again for all you do.
     
  8. achilles555

    achilles555 New Member

    Messages:
    21
    State:
    MO
    coach - not sure what you mean by "pay attention". could you please explain? thanks, ac.
     
  9. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    2 cycle engines are very simple to work on. You may can get by just by CLEANING your carbs if they have been sitting a while. You definitely have a needle not seating, letting fuel run out. Just remove the air box over the carbs, take loose the linkage, remove fuel lines, and remove the carbs. Remove the bowl off the carb that is leaking, and remove the needle and seat. Clean everything good with carb cleaner. Then blow out all orifices with an air line. Then just reassemble the carb. You might want to go ahead and check/clean the other carbs as well while you are in it this far. It's only a few hours job. If you have any mechanical skills at all, you should have NO trouble doing this. I think a 7 1/6 wrench, a phillips and a flat screwdriver, and maybe a pair of needle nose pliers is all you will need. As stated, you might just as well go ahead and replace the fuel lines and fuel filter as well at this point. Man, you can save a ton of bucks if you perform this maintenance yourself. Boat mechanics ain't cheap unless you have a friend, or a friend of a friend who can cut you a deal. What's happened is that old fuel has evaporated in your carbs, leaving behind a sticky residue that is clogging your carbs up. This is also especially dangerous to run your engine with clogged carbs as this starves the engine of fuel, or in other terms, runs too lean, which can burn a piston!

    Bill in SC
     
  10. achilles555

    achilles555 New Member

    Messages:
    21
    State:
    MO
    hey bubbakat. i asked him about setting the carbs. he said that he thought that the carbs on this motor didn't have an adjustment. he said he'd look into it, and if they did have an adjustment, 1 1/2 turns will usually be all it needs.

    what do you think?