661 Oil Test 32:1 vs 40:1 vs 50:1 ?

[Moparmyway]

The difference in volume between 44:1 and 32:1. A bit less than one ounce.

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So, youre running Lucas !!

 

[Moparmyway]

I disagree with his point (in bold). How would they get leaner? Is less fuel getting mixed with the incoming air charge or is more air being brought into the combustion chamber some how?

Here is what I believe happens ...........
The incoming mix of atomized fuel/oil meets the hot piston and cylinder wall. Some of that atomized fuel/oil mix is vaporized when it hits the hot piston/cylinder wall ; which cools the piston and cylinder wall (latent heat and change of state principles)

The hotter the piston and cylinder wall is, more of the atomized fuel that is vaporized.

Most of the different vapors do combust, but at different rates than the atomized charge.

This is where additional fuel is needed to prevent the engine from leaning out due to the increased vaporization of fuel/oil charge, necessitating more atomized fuel to combust properly.


OK, I doused my clothes with fire retardant, so let the flaming begin !!!!!!

 

[blsnelling]

Mornin' gents. It's Friday!

 

[MustangMike]

Brad, what ratio did that 441 run? I milled most of the Ash posts & beams (from logs) for my pole style cabin with a stock 441 (non-M Tronic). It did just fine, was using Stihl synthetic at 50:1 at the time.

 

[blsnelling]

I'm not sure, but would assume 50:1.

 

[bwalker]

Here is what I believe happens ...........operation the incoming mix of atomized fuel/oil meets the hot piston and cylinder wall. Some of that atomized fuel/oil mix is vaporized when it hits the hot piston/cylinder wall ; which cools the piston and cylinder wall (latent heat and change of state principles)

The hotter the piston and cylinder wall is, more of the atomized fuel that is vaporized.

Most of the different vapors do combust, but at different rates than the atomized charge.

This is where additional fuel is needed to prevent the engine from leaning out due to the increased vaporization of fuel/oil charge, necessitating more atomized fuel to combust properly.


OK, I doused my clothes with fire retardant, so let the flaming begin !!!!!!

The vast majority of the atomized fuel entering the engine vaporises as soon as it enters the motor during normal operation and your description of what happens is spot on. The main reason a two stroke smokes alot at start up is because the engine isn't warm enough and liquid fuel makes it to the combustion chamber where it doesn't fully combust. So your theory is incorrect.

 

[Moparmyway]

the engine isn't WA enough and liquid fuel makes it to the combustion chamber where it doesn't fully combust. So your theory is incorrect.

What does WA stand for ?
How does "liquid fuel" get to be liquid after the carb and its venturi atomizes it ?
Lets just pretend that your "liquid" theory is correct ............... if it were liquid, you would hydraulic lock the motor.
So your theory is incorrect

 

[bwalker]

warm enough.. Damn smart phone. After the carb fuel is in liquid droplet form.
This isnt a theory, this is how it works...

 

[Moparmyway]

The main reason a two stroke smokes alot at start up is because the engine isn't warm enough and liquid fuel makes it to the combustion chamber where it doesn't fully combust.

After the carb fuel is in liquid droplet form.
This isnt a theory, this is how it works...

First its "liquid fuel", now you are backpeddaling to "liquid droplets"

definition of atomized is; to reduce to tiny particles or fine spray .......... lets see how many more posts it takes you to clarify how your "liquid fuel doesn't fully combust" in an engine that isn't warm enough ..........NOBODY said anything about a 2 cycle smoking on startup ....we all know how the choke works........ the discussion is centered on how a 2 cycle runs leaner when it gets real hot; like milling compared to normal operation

You said that my theory was incorrect and are trying to use a cold motor at startup as your basis ?

Nothing like a deflection to attempt to make yourself look good, unless; if you get caught, of course.

 

[cuttinties]

 

[KG441c]

The hotter it gets the more evaporation will occur which would mean less lubrication if im reading right? The hotter the leaner it would become

 

[Moparmyway]

The hotter it gets the more evaporation will occur which would mean less lubrication if im reading right? The hotter the leaner it would become

My understanding is that the hotter it gets inside the combustion chamber, the more atomized fuel is vaporized, requiring additional atomized fuel for proper combustion. If you don't add additional fuel, it gets more lean as it gets hotter

(cool atomized fuel/oil hitting hot piston and cylinder walls; think of spraying water from a squirt bottle on a hot stove element. The hotter the element gets, the faster the spray flashes off into a vapor or steam)

 

[Trx250r180]

 

[bwalker]

First its "liquid fuel", now you are backpeddaling to "liquid droplets"

definition of atomized is; to reduce to tiny particles or fine spray .......... lets see how many more posts it takes you to clarify how your "liquid fuel doesn't fully combust" in an engine that isn't warm enough ..........NOBODY said anything about a 2 cycle smoking on startup ....we all know how the choke works........ the discussion is centered on how a 2 cycle runs leaner when it gets real hot; like milling compared to normal operation

You said that my theory was incorrect and are trying to use a cold motor at startup as your basis ?

Nothing like a deflection to attempt to make yourself look good, unless; if you get caught, of course.

Atomised, liquid droplet, mist.. its all the same thing. Fuel in its liquid state before it vaporizes ie turns into a gas...
And your theory is incorrect because what you describe happens in a normally functioin motor all the time.

 

[Moparmyway]

Atomised, liquid droplet, mist.. its all the same thing. Fuel in its liquid state before it vaporizes ie turns into a gas...
And your theory is incorrect because what you describe happens in a normally functioin motor all the time.

Ahhhhhhhhhhhh..................we are finally getting somewhere

1. So you do agree that the hotter it gets inside the motor and cylinder, the faster the atomized fuel vaporizes ??

2. According to you, my incorrect theory happens in a normally functioning motor all the time ??

 

[bwalker]

Yes and yes. Where you are incorrect is linking this to an increased demand for fuel under load.

 

[bwalker]

My understanding is that the hotter it gets inside the combustion chamber, the more atomized fuel is vaporized, requiring additional atomized fuel for proper combustion. If you don't add additional fuel, it gets more lean as it gets hotter

(cool atomized fuel/oil hitting hot piston and cylinder walls; think of spraying water from a squirt bottle on a hot stove element. The hotter the element gets, the faster the spray flashes off into a vapor or steam)

And this is where you go off the tracks. In a normaly running motor at normal operating temp most all of the fuel is vaporised. Under heavy load you may vaporise the very small amount fuel that typically isn't vaporised, but this would make the motor go rich, not lean.

 

[Andyshine77]

So, youre running Lucas !!

Nope! That was just some cheap oil someone gave me, it's pretty good at keeping the weeds down.

 

[Moparmyway]

Yes and yes. Where you are incorrect is linking this to an increased demand for fuel under load.

Then please explain why I need more fuel to keep cool when milling

 

[Ron660]

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$1.23 at Walmart