Yamaha F250 is putting a white smoke (allmost looks like steam) from the exhaust.
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JJF
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Mustang65fbk
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I was having I believe something similar over the summer when I'd first start up the motor for the morning and from what little research I did, it seemed to indicate that the way the motor was designed you can have excess oil buildup when lifting and lowering the motor. The article that I was reading about it said that when you see the issue, try tilting up the motor just a bit and see if it goes away. The only times I'd have that issue would be when the motor was cold, I just started it up for the morning and I'd be trolling very slowly for salmon. Whenever I tilted up the motor slightly though, it would go away, as well as when I'd be cruising it would go away completely as well.
Shannon C.
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I'm not sure if it's related but my starboard motor blew a bunch of white smoke out while running out to the tuna grounds last weekend at 5000rpm, no drop in rpm's pulled the throttles back to idle, pulled the cover off and did a once over everything looked normal, put the cover back on and right back up to 5000rpm, all good. Ran all day, got back to the slip at dark pulled the cover off and checked the oil, not a drop lost. Weird..
Oil smoke is usually not white. Rich fuel smoke is black and 'steam' is white.
The white smoke may be condensation and evaporation or excess water in the exhaust gasses. Often the steam occurs with a colder motor, similar to a dripping car exhaust pipe.
On some motor designs exhaust is discharged through several places, a more common one being the prop. If all the exhaust goes out the prop you won't see steam. On many engines there are secondary ports that vent exhaust. An example is the dump port on motors that discharge cooling water when the pressure/volume is too high. Often the dump port is fed via a poppet valve. In a dump case the water can be hot and depending on the ambient dew point, may look like steam ( it's actually probably water vapor, not steam).
So is the white smoke a bad thing? I can't say if as noted it might have been a cool day. In the warmer weather, I would be more concerned.
The white smoke may be condensation and evaporation or excess water in the exhaust gasses. Often the steam occurs with a colder motor, similar to a dripping car exhaust pipe.
On some motor designs exhaust is discharged through several places, a more common one being the prop. If all the exhaust goes out the prop you won't see steam. On many engines there are secondary ports that vent exhaust. An example is the dump port on motors that discharge cooling water when the pressure/volume is too high. Often the dump port is fed via a poppet valve. In a dump case the water can be hot and depending on the ambient dew point, may look like steam ( it's actually probably water vapor, not steam).
So is the white smoke a bad thing? I can't say if as noted it might have been a cool day. In the warmer weather, I would be more concerned.
Mustang65fbk
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To the OP, when you're running the motor and getting the smoke, is it on the trailer with a hose/earmuffs hooked up to it or is it when you're out on the water cruising around or trolling? As stated before, you can get residual oil if the motor is left either up or down for long periods of time, and if you tilt the motor slightly up or down and it goes away, most oftentimes it's likely going to be just that, residual oil. There's a multitude of threads about this on THT as well as on Google in general, I searched "yamaha f250 outboard smoke problems" and have an extensive number of links to different threads and boards about the issue. One of the replies from there is what I'd read about earlier on this summer when I looked it up personally... "With a horizontal cylinder arrangement, when the motor is tilted, oil from the walls and any drippings from the crankcase cavities onto the cylinderwalls will migrate into the combustion chambers while the motor is tilted up. That is why the motor smokes at startup. If possible it is best to shut the motor off trimmed down, let things drain a moment, then tilt it up."
I had a similar condition and hope yours is not the same (in one of my 2006 F250's). It took a awhile but I ultimately determined I was getting water in my engine oil from a leaking powerhead gasket.
I recommend you periodically check the color of your engine oil to see if it starts lightening up (brown color Vs. black).
I recommend you periodically check the color of your engine oil to see if it starts lightening up (brown color Vs. black).
It happens when it's cool to cold outside on my motor. It's a combination of moisture in the exhaust hitting cool or cold air and forming a condensate or cloud. As the motor heats up the moisture in the system gets "cooked" off quickly and it goes away.
Blue smoke is oil, black is too much fuel, white is water vapor . Green and red means you have a Jeannie living in your motor and when that happens you got a difficult problem evicting them. It's like getting roaches in your house and man it takes a while to get rid of the .
Blue smoke is oil, black is too much fuel, white is water vapor . Green and red means you have a Jeannie living in your motor and when that happens you got a difficult problem evicting them. It's like getting roaches in your house and man it takes a while to get rid of the .
I’m getting water vapor out of one of my Yamaha 150 4 strokes. Just noticed it and appears to be at low idle. I changed thermostats and impellers and I’m still getting it. Going to change poppet next.
