What, that engines should be warmed up based off the manufactures specification. Or if the motor is built, based apon what the engine builder/assembler states for the type of components inside it (IE piston and ring composition) and the related tolerances given during the build. Or that engine bearings(in a properly built motor) do not need any sort of warmup, just oil, which any primed system will give in a matter of 3-4 seconds tops. Or that the average automotive engine cylinder/piston reaches operating temperature in about 300-400 combustion cycles. How long do you think that takes at an average idle of 850 rpm…Or…
Like I said…lots of head spinning. This topic is about as retarded as the arguments over which oil weight is “the best” to run for a given engine. Shit-tons of lolz there to be had, or major headaches depending on how you look at it.
"At absolute zero (-273 degrees Celsius, -469 degrees Fahrenheit) when all atomic and molecular activity stops.
But that is not what you are asking. Motor oil, even so-called multigrade motor oil like Mobil 1 5W-30, looses viscosity the hotter it gets. Your oil is thickest (highest viscosity) when it is coldest.
The reason to warm up the engine before “gettin’ on it” is to allow thermal expansion of the block to occur. Combustion temperature will heat the pistons, and make them grow in diameter, very quickly and effectively. If the block is not at operating temperature, you can scuff or even seize some pistons, not a pleasant occurrence.
So you should really be watching the coolant temperature, and let it get above 160F (the closer to your normal operating temperature the better) before hammering the throttle.
Bearings love lots of cool, thick oil, and as long as the oil pump can pump it, the cooler the better.
(Please note, in a past life I was the Director of Research and Development for the Clevite Bearing Co., hence my screen name.)"
If oil is thinnest at cold temperatures and thickest at operating temp according to 10w-30 or any other viscosity index… Why does it flow out of the motor easier during an oil change and is slow to flow when cold, completely counter intuitive to the index.
You guys might want to read up on what the numbers on the bottle mean
I don’t have it backwards, that’s the point.
Thicker or heavy viscosity oils will take longer to flow through the orifice in the viscometer and end up in higher number ranges such as SAE 50 or SAE 60 for example. If an oil flows through faster being thinner/lighter then it will wind up in a low number range such as SAE 10 or SAE 20 for example.
This allows the engine to get quick oil flow when it is started cold verses dry running until lubricant either warms up sufficiently or is finally forced through the engine oil system. The advantages of a low W viscosity number is obvious. The quicker the oil flows cold, the less dry running. Less dry running means much less engine wear.
The viscosity grade (for example, 5W-30) tells you the oil’s thickness, or viscosity. A thin oil has a lower number and flows more easily, while thick oils have a higher number and are more resistant to flow.
Water has a very low viscosity – it is thin and flows easily. Honey has a very high viscosity – it is thick and gooey.
The viscosity will determine how easily the oil is pumped to the working components, how easily it will pass through the filter, and how quickly it will drain back to the engine. The lower the viscosity the easier all this will happen. That is why cold starts are so critical to an engine because the oil is cold, and so relatively thick.
So my question stands, why it flows easier when warm even though it’s viscosity is higher, which means it’s thicker. :ponder
First number on the bottle is at freezing temp IE “5”, second number on the bottle at operating temp, IE “30”.
Oil is thin at start up so it actually gets flowing through the motor due to paraffin additives in dino oils and natural properties in real synthetics.
If water gets in oil , unless its mixed to the point that it makes a vanilla shake lol I’m not sure . But if its in thee and seperated it will freeze at a water freeze point .
Vlad, there is NO relation between the “W” number and the non “W” number-
“W” numbers=cP=centipoise
non “W” number-cSt=centistrokes
A 5W30 oil is not thicker at higher temps vs. 32 degrees. Sure the viscosity number is higher, but that’s just it, it’s just the NUMBER. It’s a number that references a different meaning (cSt). How do you not understand this?