OK so I am ashamed to admit it but....

Discussion in 'Outboard Maintenance' started by snooknreds2, Apr 14, 2009.

  1. snooknreds2

    snooknreds2 Well-Known Member

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    I think I blew my head gasket.... :mad:

    when I clean my boats and feel lazy sometime I leave the ear muffs hooked up to the motor.  I have a routine in practice for years for this though.  If I do leave the muffs on I will leave the hose attached so that I remember to take the muffs off later.  This has worked great since I am the only one that uses the hose.  Well since we moved last month the hose is now being used by more than one person.  Apparently the hose got disconnected from the ear muffs with out me knowing.  

    So... Sunday night I am going to go snook fishing for an hour or so.  Get to the ramp choke on, no gas and the motor starts up as usual and then dies. HHmm that is funny.  Oh well it has sat for a while must just be stiff in the joints.  Fire it up again.  Idles for a few seconds and then dies.  Choke back on and turn the key.  Starts up, white smoke :eek: comes out and idles for a second or two then dies. Ok give it some more gas.  Turn the key, starts up , revs high (as it should at this point), let off the gas and it idles for a second before dying.  Try the same thing again but this time open the gas up and it bogs out, still with white smoke.  
    Long story short.  
    Choke on, with gas or with out gas, dies out.  Give it gas and it bogs out.
    Choke off, with our with out gas, dies out.  Give it gas and it bogs out.

    So remember those ear muff.. Well I get back home and they are still on the lower unit!!!!   Pushed back, not quite covering the water intake on the lower unit but still some what covering it.  Get it back home and try it again, out of the water.  Not as bad but still the same story.  Ok check the plugs.  Dirty, like it is mixed rich, but not water....  HHmm
    Now I am puzzled??  Idle and it dies out while producing white smoke.  Give it gas and it revs up with white smoke then bogs out.  Gotta be a blown head gasket right???  But then no water on the   plugs suggest that the head gasket is not blown.  Can some one help me make sense of this?  PLEASE!!!!

    OH BY THE WAY...  while trying to start the motor in the water it was pissing strong, as usual.
     
  2. Brett

    Brett > PRO STAFF <

    Easy to check a head gasket, compression test, do it first.
    Water getting into the firing chamber can come from more than just
    a head gasket. If you didn't get a chance to run the motor except
    trying to start it, I don't think you had a chance to overheat.
    You said the boat has sat a while. Water in the fuel? Try a fresh mix.
    Last tank might have been E10 that sat and absorbed water.
    Old friend was a bit forgetful with the rinse muffs. His solution
    was a cord that tied to the muffs and looped over the throttle.
    Seeing the cord draped across the cockpit and throttle at the ramp
    reminded him to remove it before starting.
     

  3. B.Lee

    B.Lee Well-Known Member

    If the engine was pumping water, and you could see it via the tell tale stream, tehn the muffs were just in teh wrong place, but not obstructing your water flow. Even so, if they were obstructing your water flow, it would take a few minutes, especially at idel at the dock, to overheat the engine enough to cause any damage.

    What you are describing is old, stale fuel. With ethanol blended fuel these days, that problem becomes worse and comes on quicker.

    Last time you flushed it, did you leave fuel in the carb or pull the fuel line and run it out? If you left it, you'll need a carb cleaning. The engine is dying from fuel starvation. The primer bypasses the pilot jet (low speed jet) and feeds enough fuel to fire the engine, then it dies once that is burned.

    These engines do not have a choke, they use a primer circuit. When you pull the "choke" knob, it shoots a stream of fuel into the carb throat, and fires the engine with a richer fuel mixture.

    Get some fresh fuel and try it again. I think you're going to need ot clean the carb though, easy fix. Check the compression if you still are in doubt about the head gasket.
     
  4. snooknreds2

    snooknreds2 Well-Known Member

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    YEA YEA!!!!! Thank you guys for your quick response. I really was so heart broken that I couldn't think straight enough to consider a comp check. Read your replies, went to the tool box and then out tot he boat...Compression check was good, both cylinders are right at 120 PSI. I am going to get new gas and see if that makes a differance.


    The other thing that I thought it might have something to do with is the fact that the seal on the fuel filter bowl is leaking slightly. I thought maybe that was not letting it build up pressure in the system to force the gas through. Is this something that I should be concered with or just leave it alone. My real only concern with it is that when you pump the ball it forces small amounts of gas out of the top of the bowl and I just dont like having gas drip down into the motor
     
  5. Brett

    Brett > PRO STAFF <

    Leaking gas is a fire hazard, not good.
    Ruin your whole year, hmmm?
    Time to rebuild the carb?
     
  6. B.Lee

    B.Lee Well-Known Member

    That's not good, for two reasons. First and foremost, like brett said, an engine fire will ruin your day,and two, a leaking fuel pump will not produce the correct fuel pressure or volume to run properly.

    It could be as simple as a fuel pump rebuild, since you are starving the engine for fuel, that might fix it. A good carb cleaning never hurt anyone though.
     
  7. snooknreds2

    snooknreds2 Well-Known Member

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    Looks like plugs, carb clean, and fuel filter bowl are in my future
     
  8. iMacattack

    iMacattack busy, too busy

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    add fuel treatment to that list! E-Fuel, E-Sucks... :mad:
     
  9. snooknreds2

    snooknreds2 Well-Known Member

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    OK so now I am puzzled...

    I got new plugs, new gas (along with oil) and my motor still dies at an idel.  It is not as bad as it was (there was for sure some water in the old gas)

    But it is still doing the same thing.   Ultimately I would say it sounds like it is not getting enough gas.  

    If I read this I would tell someone else to clean the carb at this point but for some reason I do not think that is what is going on (maybe I just want to think that I dont know...I do not like playing with carbs)

    Any other thoughts as to what else it could be??  

    The other weird thing is that the ball will not stay hard (I dont know if it ever did) but now it takes for ever to get the ball hard (which as I type this makes me picture the jet in the carb all gunked up not letting fuel flow through it)


    Should I just man up and take the carb off and clean it?  I can do it and have in the past.  I just suck at tuning them once I put it back on :(
     
  10. snooknreds2

    snooknreds2 Well-Known Member

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    Oh and I fixed the fuel filter bowl issue. Turns out there was no gasket in place like there should have been. I just took the one off my other motor that is waiting to be used for the crack-noe.
     
  11. snooknreds2

    snooknreds2 Well-Known Member

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    OK I think it might be the fuel pump not the carb... any thoughts???
     
  12. Gramps

    Gramps Living &amp; Dying in 3/4 Time

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    Does any fuel leak at the engine connector? I had similar issues; ball going soft, did not want to idle and the engine died while running at higher RPM's (Matt knows he escorted me 12 miles). Turned out my connector was bad, it did not create a tight seal. No seal = no vacuum for the fuel pump.

    By the way Yamaha and Mercury use the same fitting.
     
  13. beavis

    beavis Well-Known Member

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    i have had problems with o-rings on the connectors not letting the fuel ball get hard. easy fix to rule that out.
     
  14. snooknreds2

    snooknreds2 Well-Known Member

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    OK so it turns out that the anwser is what I thought, and was hoping for. I just can not tune a carb for Shizit!!! :D :D

    My buddy came over. 10 Mins of BS then 5-10 mins of him working on it and it works. Go to the boat ramp and put the boat, still attached to the trailer, in the water. Long story short we made some few minor adjustments and I am pretty sure it works.

    Why did'nt I go for a spin you might ask.... Well the throttle cable came undone from the actual throttle lever in the whole process. So I had to go back to lowes and get a couple C-clips. They are not stainless but will do for now untill I can go to west marine or something.

    I might go put her in tonight.. still debating it [smiley=1-mmm.gif]
     
  15. snooknreds2

    snooknreds2 Well-Known Member

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    The idle screw needed to be adjusted and I did not think of that since I had not touched it. HOWEVER, it is attached to the fuel pump cover plate which I did remove. My thought is that the tolerance in the screw holes was enough to when I screwed it back on it moved over the 1/16-1/8 inch that the idle screw needed to be adjusted... Oh well at least it is fixed and I am that much closer to being able to do it on my own next time... Kinda embarrassing though. I can rebuild a motor. I can rebuild the carb.. Just can not tune it for the life of me :mad:
     
  16. paint it black

    paint it black Paddling away...

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    It's definitly a carb issue. It happened on my skiff, it happened on chris's boat, and it happened on my 7.5. It was the carbs on all three.
     
  17. paint it black

    paint it black Paddling away...

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    My Mariner, and my Mercury don't use the same fitting. The controls on my Mariner as well as harness are Yamaha parts. The local marine store told me that Mariner was actually both a Yamaha and Mercury somehow. Yamaha built, Mercury parts or something like that. But both of my motors take different gas plugs.