gas leak on a 8 hp mercury?

Discussion in 'Bubba's Outboards' started by BassMassey, Feb 6, 2009.

  1. BassMassey

    BassMassey Well-Known Member

    Messages:
    1,883
    State:
    Oconee
    well i was just out looking the boat over and noticed the lil bit of water sittin in the back of my boat had a lil slick on it. I had the motor trimmed up and i usually leave it down when at the house. I pumped the primer bulb to make sure it still had good pressure and sure enough gas started dripping out of the pull knob on the motor? The ball stayed hard though like i still had good pressure. I take the cap off the motor and look things over and give the bulb some more pumps to see if i can tell where the it's coming from....im not very motor savy, but seems like it's coming from the carb. I go to pull start the motor and she started right up like normal. Now I think this may have been going on as long as late summer now I think about it. when sitting on one spot idling on the lake the motor has been leaving a pretty good slick on the water.....probably more then a normal 2-stroke should......anyway what do you think we're looking at? and how much? lol......
     
  2. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    If there is not a fuel line leak, MOST LIKELY the carb needle is not seating in the seat correctly, probably due to a tiny bit of trash in it. VERY simple fix. Pull the air box that covers the carb. Pump the bulb. If you see fuel coming out of the little brass tube, that's the problem. If so, remove the carburator. Then, remove the bowl from the bottom of the carb. This will allow access to the needle and seat. You can then blow it out with an air line, and the needle should seat well again.

    Bill in SC
     

  3. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    BTW Lil Chiefin. That is such a simple job, YOU can do it with NO trouble. Don't pay anyone a wad to let them do this. Probably all you will need is a 7/16 wrench and a philips screwdriver. You WILL also have to disconnect the linkage which is just a cotter key. Just try hard not to mess up the gaskets. If you do mess them up, they are quite cheap. Wish I were there, or you were here with it. I'd do it for you for nothin'. Maybe an hour job at the most. 2 strokes are VERY simple to work on.

    BB
     
  4. BassMassey

    BassMassey Well-Known Member

    Messages:
    1,883
    State:
    Oconee
    thanks bill......i hope it's that simple....i hate it when something goes wrong with the boat.....can't quit thinking about it. i don't know if im that comfortable pulling parts off the motor though? Im in pretty good with the mechanic at the marina across the street though, he's guided me through a fuel pump replacement, and wiring my boat up........but i've never actually took my boat there for service, he's $80/ hr. He did run my motor for me before i bought it........said if im not gonna buy it , he is........so i bought it, lol. do you think it's really that easy of a fix that i could manage? I guess i could take a look at it tomorrow, i just don't want to tear anything up......
     
  5. BassMassey

    BassMassey Well-Known Member

    Messages:
    1,883
    State:
    Oconee
    what's the linkage? and a cotter key? lol
     
  6. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    Oh yeah, you will have to disconnect the fuel line. Just a simple clamp.

    BB
     
  7. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    <do you think it's really that easy of a fix that i could manage?>

    I think so.

    <what's the linkage? and a cotter key? lol >

    The linkage is the rod that opens and closes the carb. When you twist the throttle, the linkage actuates the carb. In other words, the linkage connects the throttle with the carb. It's usually attached to the carb with a cotter pin. This is a tiny metal pin that goes through the shaft where the linkage hooks to the carb. you can use needle nose pliers to bent the cotter pin straight, to pull out of the shaft with the pliers. To re-install, just push the cotter pin back in and bend over one of the two arms on it so it can't come out. Just pull the cover off the motor tomorrow and look at it. It's pretty self explanatory. If you see anything you don't understand, hit me with an E or PM. First things first. Pull the air box so you can look into the throat of the carb. Pump the bubble on the gas line. If fuel pours out of the carb, do the things I just described. You got my number, call me if need be. I can talk you through it.

    BB
     
  8. BassMassey

    BassMassey Well-Known Member

    Messages:
    1,883
    State:
    Oconee
    i just popped the hood off and took another look........ain't nothin but phillips head looks like to me....I just don't know motors very well at all. But the mechanic across the street did help me with the fuel pump and that ended up being a breeze......well i had to run over there a couple times to ask some more questions or borrow a hose clamp, lol. so you think it's pretty probable it's that pin is dislodged? i haven't checked any of the lines really other that what you can see when you pull the hood off......sure do appreciate all the advice bill! i'll take a better look tomorrow
     
  9. roadkill636

    roadkill636 New Member

    Messages:
    551
    State:
    warrenton misso
    if the motor was tilted up the carb floats will leak fuel out of the carbs....
    leave the motor in the down posion when not in use
     
  10. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    This is true, but he said it was leaving an oil/fuel slick when he ran it last. Most likely what I said with the needle and seat. Never hurts to remove the bowl for a periodical cleaning anyhow. So simple a caveman can do it. BTW: ALWAYS crank the motor with it all the way in the down position. The carb is gravity fed, and being in the down position is the best cranking position.

    Bill in SC
     
  11. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    <so you think it's pretty probable it's that pin is dislodged?>

    NOT a pin, but the needle. See pic. The seat is fixed in the carburator. The needle floats on a tiny pin that is held on with a small clip. MOST likely, the seat has a tiny pieces of debris in it, that is not allowing the needle to seat, thus not cutting off the fuel flow, and not allowing the float to rise up and stop sending fuel. Sounds complex, but once you look at it, mighty simple.

    http://out2win.com/catalog/images/TIL-233-665.jpg

    Bill in SC
     
  12. BassMassey

    BassMassey Well-Known Member

    Messages:
    1,883
    State:
    Oconee
    well it's been leaving a lil slick since about last october......i didn't think too much about it and just thought it was because it was a 2 stroke......i usually always store the motor in an upright position......the other day i left it up after getting measurements for the rod rack and never put it back down....i go out today and smell gas and notice a the lil bit of water in the back of my boat had gas and oil sitting on the top of it..........now when im fishing i lift the motor all the way up out of the water and leave it like that until i motor to another spot and have never noticed fuel leaking out of the primer pull? or is it only a problem after long periods of the motor being jacked up?.......
     
  13. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    Imagine a glass of water. When you tip it on it's side, water runs out. If your float is sticking due to the needle not seating, gas pours out of the carb. If you have a slick behind your boat, unburnt fuel/oil is being dumped in the water. I recently disassemble one of my carbs to do exactly what you most likely need to do. I had a slick behind my boat, and the motor was running a tad rough at idle. Problem was debris in the seat. Not much else really, that it could be other than a leaky line. PUMP THE BULB with the motor cover OFF and you will see exactly where it's coming from. If it's pouring out of the carb itself, it's the problem I described.

    BB
     
  14. BassMassey

    BassMassey Well-Known Member

    Messages:
    1,883
    State:
    Oconee
    yeah i think you're right bill......a girl i work with husband works on boat motors.......i just talked to him and he said exactly the same thing.....although im still not that comfortable pulling parts off my motor yet, im gonna take it over to his place monday and he's gonna clean my carb out, change my lower unit oil, and change the plugs for a fifty....im gonna pay real good attention and ask questions so next time i can do it myself.....
     
  15. BassMassey

    BassMassey Well-Known Member

    Messages:
    1,883
    State:
    Oconee
    i hear ya on the rough idling too! when im runnin wide open then cut it down to go under bridges n no wake zones my motor sounds like it ate a couple cans of beans.......once i give it a lil gas it runs fine though.........appreciate all the good info bill.....just wish ya lived a lil closer, lol....good luck today fishing against rivercats n crew........
     
  16. BassMassey

    BassMassey Well-Known Member

    Messages:
    1,883
    State:
    Oconee
    hey bill.........i've heard it's pretty easy to make my 8 hp run as fast as a 15 hp? what all is involved with that? is it just a bigger carbuerator.....
     
  17. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    I'm not sure with your engine, but with some of the smaller bore engines, it is simply just a carburetor change, to increase hp.

    Bill in SC
     
  18. roadkill636

    roadkill636 New Member

    Messages:
    551
    State:
    warrenton misso
    pay a lot of attention when he is re installing the lower unit and how he alines the driveshaft, water pump tube, and the shift shaft all at the same time :)
     
  19. Bill in SC

    Bill in SC New Member

    Messages:
    4,451
    State:
    South Caro
    He's not removing the lower unit, just changing the fluid in it.

    BB in SC
     
  20. BassMassey

    BassMassey Well-Known Member

    Messages:
    1,883
    State:
    Oconee
    he looked at it yesterday......the carbeurator was fine.....he said if it drips when the motor tilted that's pretty normal........my plugs were shot, i think that was why it was idling a lil rough.......changed my lower unit oil......which was due for a change......had a lil water in it, but no metal shavings or anything like that........