What happens to the Boundary Layer?

[Dr. T]

After it's used? Does it fluff away or char the surface? Where does it go when it's used?

 

[cryptokid]

if you are refering to zinc, which i think you are, i believe zinc just goes away, like how cotton candy does when its being eaten by me.

 

[MolaKule]

The boundary layer refers to the respective surfaces of two adjoing metals. Boundary layer lubrication simply means that the hydrodynamic film has been ruptured and we are now relying on another mechanism to keep the surfaces from wearing into each other, a result called scuffing and galling. Anti-Wear and Extreme Pressure additives keep this surface wear from ocurring. For Moly, or Antimony, or ZDDP, these chemicals deposit themselves on the surfaces and form a multi-layer film. Under pressure, this multi-layer film turns into a plastic or molten glass-like substance which keeps the surfaces "riding on" each other and not gouging "into" each other.

 

[jason07-1zzfe]

quote:

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Originally posted by MolaKule: ... these chemicals deposit themselves on the surfaces and form a multi-layer film. Under pressure, this multi-layer film turns into a plastic or molten glass-like substance which keeps the surfaces "riding on" each other and not gouging "into" each other.

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I think he meant what happens after what you just described. If he didn't... I'm asking now. I would imagine that would wear off eventually. Then where does it go? Are those particles harmless? I assume they are no longer usefull but are they still detectable in analysis? Is that why, I think you, said you can still have ZDTP in used analysis but it may not necessarily be active.

 

[MolaKule]

You're right Jason. Ok, sorry, I was on another level. Some of the Anti-Wear additives "shear-off" and some go back into solution. Some of the original additive components "decompose" never more to help with Anti-Wear. A small fraction of the decomposition process is that of evaporization. Let's take ZDDP for example. It is made up of zinc, sulfur, and phosphor molecules. The sulfur helps the zinc and phosphorus "bond" to the metal, creating the multilayer film. The zinc films will melt at high temp or pressure, creating the plastic layer. The phosphor molecules contribute to the EP properties and allow more "slip and slide" when high pressures are present. Mechanical shear will tend to "scrape" some of the molecules off the surface. High temperatures will cause evaporation (decomposition) of some of the sulfur and phosphorous molecules. When the zinc is sheard from the films, some of it just goes into the oil and never "rebonds" to the metal; it doesn't hurt anything, in fact zinc is a "base" metal helps to control tbn somewhat and keep acids under control. Now some of the sulfur and phosphorus that don't decompose as evaporates, turn into acids when combined with moisture. However, these acids are very mild and are very often neutralized by the calcium, magnesium, and moly (if present). Jason is correct, zinc will still show up in an analysis, even though a small percentage of the zinc is just floating around not doing much, kinda like me when I'm swimming at the YMCA.

 

[Patman]

quote:

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Originally posted by MolaKule: Jason is correct, zinc will still show up in an analysis, even though a small percentage of the zinc is just floating around not doing much, kinda like me when I'm swimming at the YMCA.

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A useless swimming MoleKule!

 

[dragboat]

I wish the Forum could collectively chip in and supply < MolaKule > all the oil he ever needs for posting on this Forum. Here, He has no equal in his knowledge and never ending willingness to share it. Thanks MolaKule [ February 04, 2003, 06:52 PM: Message edited by: dragboat ]

 

[S2000driver]

None of this stuff ever happens in *MY* engine

 

[buster]

quote:

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A useless swimming MoleKule!

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You guys crack me up.....

 

[Patman]

quote:

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Originally posted by dragboat: I wish the Forum could collectively chip in and supply < MolaKule > all the oil he ever needs for posting on this Forum. Here, He has no equal in his knowledge and never ending willingness to share it. Thanks MolaKule

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I agree, his knowledge is amazing! Problem is, how would we decide what oil to buy him! We can't even agree ourselves on what oils to run!

 

[G-MAN]

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Originally posted by Patman: I agree, his knowledge is amazing! Problem is, how would we decide what oil to buy him! We can't even agree ourselves on what oils to run!

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We'd just have to go to various suppliers and get the very best ingredients, the most costly PAOs, the most exotic esters, etc. Then we create a new brand: "MolaKule HyperSyn." It has a VI of 250, no polymer VI improvers, HT/HS of 5+, Noack of <1%, Cp at -100*C of 2000, and a cSt at 100*C of 12.49. In addition, the oil smells like a pina colada and its color changes based on your mood when you put it in. Recommended change interval is 100,000 miles and it costs $63.00 per quart.

 

[MolaKule]

"A useless swimming MoleKule!" Yep, that's me. GMAN, Yeah, but can I get the oil at the local Walmart? You guys give me too much credit, but I am happy to share the info.

 

[G-MAN]

quote:

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Originally posted by MolaKule: GMAN, Yeah, but can I get the oil at the local Walmart?

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They'll probably demand deep discounts from us, so you should be able to get it for $55.95/qt.

 

[MV Oil Fanatic]

quote:

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Originally posted by buster:

quote:

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A useless swimming MoleKule!

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You guys crack me up.....

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Now that's not very nice. I use S2000 BTW in my Beamer without ever having had a problem of any type.