Nope, sorry. I assume you typoed that it lowers boiling points, but even if you said it raised boiling points you'd be wrong. Pressure is the only thing that raises boiling temps.Originally Posted by japrules
Water pumps don't need lubrication. The bearing for the impeller shaft is behind the shaft seal and lubricated by the engine oil.
Today’s motorcycle engines aren’t running hot, they run at ~220 because that’s how they are designed to operate. More on that below.
Here's what water wetter REALLY does. It is a surfactant, which means it lowers the surface tension of water. What does that mean? Well, lemme put it this way - bar soap doesn't actually clean your skin, water does. The problem is that normally the surface tension of both your skin and the water prevents the water from getting "into" your skin enough to remove oils and dirt. If you lower the surface tension of the water it can become thinner and get in between your skin and the oils and dirt you want to remove. Bubbles are a natural result of soap, but they aren't made of soap, they are made of water. Normally the surface tension of water is such that the surface breaks before it is stretched thin enough to be supported by air and form a bubble. If you lower the surface tension it can be stretched thinner without breaking and a bubble is formed.
Another example of what surface tension does is when you wax your car. Before waxing it doesn't "bead" water, right? The water spreads out smoothly. When you wax your car one of the results is the surface of the paint now has a higher surface tension and resists the water, which results in "beading". This means that the surface also resists other contaminants, which is how the wax protects the paint. The beading is a result of the surface tension of the water making it want to form a sphere, a sphere being the shape that has the least amount of surface area per amount of volume.
OK, back to the point...in order for water to cool an engine you must have heat transfer in three places - from the engine to the water, then from the water to the radiator, then from the radiator fins to the air. We'll forget about the third for now since we're talking about the water, not the condition of the fins.
So, we agree we need heat transfer. Heat is most efficiently transferred when objects touch, the more surface area they touch, the more energy they transfer. Back to the water beading on your fresh wax job - when the water beads (high surface tension) only a very little of it is actually touching the paint and available to accept heat transfer, whereas before you waxed it (low surface tension) the water spread out and there was more surface area contact, which would facilitate better energy transfer.
Inside your engine there is natural surface tension in both the aluminum and the water...they are resisting contact and therefore resisting energy transfer. The surfactant lowers the waters surface tension and makes it "dig into" the aluminum better. This increase in surface area contact reduces hot spots and makes for better energy transfer both from the engine to the water and the water to the radiator. Once the radiator has the energy, the fins must be in good enough shape to get the energy to the air. Again, more fins and/or straighter fins = more surface area exposed to the air.
So, in summary, all water wetter does is lower the surface tension of the water which increases surface area contact between the water and the aluminum which in turn increases energy transfer between the two. The trick is making a product that lowers the surface tension without allowing the churning of the water pump to create foam or bubbles.
A couple other general points about engine temp:
1) As I said above, these bikes are designed to run hot. You want it to run as hot as possible, as long as the temp levels off and doesn’t continue to climb. Why? Because another thing that increases energy transfer is a disparity between the temps of the two objects. The cooler the water in the jackets is, the more heat it takes from the cylinder, which is heat that is now no longer pushing the piston down. When you use products like this to lower engine temp, what you’ve effectively done is allow yourself some headroom to do mechanical things that increase HP (which increases heat by-product) without overheating the engine. As long as it isn’t boiling over, don’t lower engine temps just for the sake of wanting the engine to run cooler, the result will be a decrease (albeit, a very small one) in power output.
2) If you are sure your cooling system is operating at its peak and you still can’t control engine temps, the possible culprit is pre-detonation of the fuel (the fuel burning from the heat in the cylinder before the sparkplug fires). Even if the engine is bone stock and runs fine on pump gas on the street, the constant high RPM use of track use allows less time for the excess heat to dissipate. This increases cylinder temps, which can lead to pre-det, which leads to higher temps, which leads to more pre-det, etc, and your coolant temp skyrockets. The answer could be higher-octane fuel. Octane is a measure of the fuels ability to resist pre-detonation. Because higher-octane fuels actually resist burning, ideally you want to run the lowest (yes, I said lowest) octane fuel you can without getting pre-detonation. This will result in an increase in power output. Putting higher-octane fuel in an engine that doesn’t exhibit symptoms of needing it will result in a decrease in power output (oxygenated fuels excepted – this is another discussion). You put high-octane fuel in high HP engines because they make lots of power, not the other way around.
3) Other factors that increase engine temp are lean mixtures, compression increases and timing advances.
Your homework for tonight is to read chapters 4-7 on thermodynamics. Class dismissed.
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