Well that didn't go like it was supposed to... motor trouble question?!?!?!?!

tod osier

tod osier

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Today is one of the last days I'll be able to hunt the coast for ducks and brant given my plan to move the Snow Goose out to Wyoming. The morning started perfect - cold, good tide, clear and calm. The harbor was iced over as the tide was running out.

I had a little trouble getting the motor to run on the trailer and it stalled when I launched it and again didn't want to come to life and was running rough. I made it out to the channel and the motor was obviously not running right. On very cold mornings over the past 20 years with this motor it has not been uncommon to have it be balky and run rough until it warms up (1-3 minutes) - once it gets warmed up and you give it a little throttle it runs perfect the rest of the day.

Today when it was running rough and I couldn't get it to behave I pulled the cowl off and a steady stream of fuel was running out of the carb (I think out of an adjustment screw, but cant be sure, it was dark). At this point it had run for several minutes - way past the period when it should be settled down. I limped back to the launch and got the truck and once on the trailer again and tried to start it. Fuel running out of the carb again. I just got home and tried it in the driveway, no fuel and it runs perfect, motor was warm to the touch under the cowl. I've never seen this with the fuel before. THOUGHTS?!?!? Obviously, I'm thinking there was ice in there that melted and what I saw today was an exaggerated episode of what I'd say was common, but the fuel pouring out then, but not now is my question.
 
Stuck float, or ice in the carb throat. A tiny bit of the water in the gas freezes in the carb, stuck float. If you keep the motor in a warm garage before hunting, when you take it out into the cold condensation forms. Then ice builds up around the butterfly when it starts, effectively choking the motor. I've had both happen, admittedly with 2-strokes. Lots of gas leakage either way.
 
SJ Fairbank said:
Stuck float, or ice in the carb throat. A tiny bit of the water in the gas freezes in the carb, stuck float. If you keep the motor in a warm garage before hunting, when you take it out into the cold condensation forms. Then ice builds up around the butterfly when it starts, effectively choking the motor. I've had both happen, admittedly with 2-strokes. Lots of gas leakage either way.
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I felt like it had plenty of time to thaw, but I should have given it some more time on the trailer at the launch. The amount of fuel pooled in the motor wasn't encouraging as far as letting it sit there and idle :). I've always been afraid of this carb since it is supposed to be sorta legendarily difficult to adjust, so I've been hands off on it, although I do everything else on the motor. Last time I had the carb rebuilt it was embarrassingly expensive, but we have a real shortage of good Yamaha techs that will take work in this area. I had to beg the guy and schedule months in advance.
 
Steven Alexander said:
If the float sticks open, it overfills the bowl and runs out of a weep-hole in the side. If it's running out of multiple carbs, your throttle cable/controls may be out of adjustment.
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Just running out of the bottom carb. That weep hole sure was doing its job. :) Thanks for the info. As much time as I've spent with motors, I just haven't seen or noticed this.

The question is if I turn and burn and try to get out today or give it a go tomorrow on the closer.
 
SJ Fairbank said:
Look at the bright side. You didn't have a fire. Of course, that would have solved your 12" trailer tire dilemma.:oops:
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:oops: is what I was thinking 🔥. Just to paint a picture you can enjoy when the motor was giving me trouble - I was laying there drifting out to sea trying to evaluate the motor under the railroad bridge and the metro north flies by right overhead and blows his horn. Nice! Beaver cut his foot on an oyster too, so I have blood everywhere. Boo Hoo. I guess I'll have to hunt tomorrow morning with everyone else.

I have the tires sitting in the shop and bearing and seals being delivered today, but I'm not doing that job until

To be honest, I was a little excited thinking about repowering. I may just do that anyway. That motor is 25 years old and had a lot of salt usage. The bolts that I commonly remove like for the thermostat and to drop the lower unit when I do maintenance come out, but I bet there are a lot of stuck bolts in there if I ever needed to do serious work on it.
 
tod osier said:
The question is if I turn and burn and try to get out today or give it a go tomorrow on the closer.
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Does this carb have a drain screw on the bottom of the bowl? (that you can get to) If so, drain that bowl and go. :cool: After all it's not like it's my butt on the line.
 
tod osier said:
Just running out of the bottom carb. That weep hole sure was doing its job. :) Thanks for the info. As much time as I've spent with motors, I just haven't seen or noticed this.

The question is if I turn and burn and try to get out today or give it a go tomorrow on the closer.
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Take the bottom carbs bowl off, unstick it, and hit it with carb cleaner. Probably got a tiny piece of trash in it somewhere, or as was mentioned, some condensate froze in there and stuck it. Either way, it's a relatively easy fix.
 
Huntindave McCann said:
Does this carb have a drain screw on the bottom of the bowl? (that you can get to) If so, drain that bowl and go. :cool: After all it's not like it's my butt on the line.
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Yes, I have drained it before. I just had no idea the volume of gas that could come out of the carb in such a short time. Where I was planning to hunt I am motoring out to hunt offshore islands in January amongst flows of salt ice. So, I am pretty careful.
 
Steven Alexander said:
Take the bottom carbs bowl off, unstick it, and hit it with carb cleaner. Probably got a tiny piece of trash in it somewhere, or as was mentioned, some condensate froze in there and stuck it. Either way, it's a relatively easy fix.
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Here is a pic. I don't think it is easy to do that, but like I've said I'm scared of this thing and always tip-toed around it.

1737125083651.jpeg
 
tod osier said:
:oops: is what I was thinking 🔥. Just to paint a picture you can enjoy when the motor was giving me trouble - I was laying there drifting out to sea trying to evaluate the motor under the railroad bridge and the metro north flies by right overhead and blows his horn. Nice! Beaver cut his foot on an oyster too, so I have blood everywhere. Boo Hoo. I guess I'll have to hunt tomorrow morning with everyone else.

I have the tires sitting in the shop and bearing and seals being delivered today, but I'm not doing that job until

To be honest, I was a little excited thinking about repowering. I may just do that anyway. That motor is 25 years old and had a lot of salt usage. The bolts that I commonly remove like for the thermostat and to drop the lower unit when I do maintenance come out, but I bet there are a lot of stuck bolts in there if I ever needed to do serious work on it.
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Get 'er going for the last day, then .....Repower!!!!! Fresh start with a freshwater motor. Good thinking.

You'll slay them tomorrow. The duck gods owe you one.
 
tod osier said:
Yes, I have drained it before. I just had no idea the volume of gas that could come out of the carb in such a short time. Where I was planning to hunt I am motoring out to hunt offshore islands in January amongst flows of salt ice. So, I am pretty careful.
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Years ago I experienced an engine/fuel fire on my fathers runabout. The fuel lines were old and cracked. We had nothing to extinguish the flames except to splash river water using our hands. Luckily the river was shallow and we could stand behind the motor. After the fire was out, I can't remember if I restarted the engine or if we floated back to the landing.
 
That carb setup does look complicated. I'd bring it inside, buy new gasoline, flush out the old and make sure to leave the engine outside to cool to ambient temps before going to the launch.
 
Huntindave McCann said:
Years ago I experienced an engine/fuel fire on my fathers runabout. The fuel lines were old and cracked. We had nothing to extinguish the flames except to splash river water using our hands. Luckily the river was shallow and we could stand behind the motor. After the fire was out, I can't remember if I restarted the engine or if we floated back to the landing.
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There really is nothing scarier in a boat than fire. Counterintuitive, but terrifying. Had a couple small ones, seen some big ones. No bueno.
 
Tod,

Take this brass screw out of the bottom bowl, and blast up in there with a new can of carb cleaner. Slap that linkage from closed to WOT several times. Blast carb cleaner again. Then re-prime your fuel line/bulb, and see if it keeps weeping out.
 

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SJ Fairbank said:
That carb setup does look complicated. I'd bring it inside, buy new gasoline, flush out the old and make sure to leave the engine outside to cool to ambient temps before going to the launch.
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I've had some fuel in water issues in the past. I have a water separating filter on it and I keep new gas in the motor.

Because the carb issues in the past and how expensive a rebuild is and the fact that the yamaha tech that has been rebuilding it says the ethanol fuel is to blame... I built a special little tank that I run fresh non ethanol fuel into the motor every time before I shut it off. For anyone not aware, the pumps here mandate ethanol, so there are no pure gas options from a pump here only canned (I import from out of state).

Boat was cold in the barn and ran beautifully a couple days ago.
 
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