Motor Oil 108
Chapter Eight. Odds and ends.
第八章。零碎东西。
I have some stories that I collected. First，my architect drives a big SUV. He was running with Mobil 1 brand 15W-50. He changed it to Pennzoil Multi-grade (mineral oil based，non—synthetic，cheap) 5W-20 at my suggestion. His gas mileage went from 10 to 13 MPG around town. What really impressed him the most was the “robust” increase in “get up and go." He changed from a thick synthetic to a thin mineral oil. His venue is stop and go city traffic in Florida, mostly short trips. The oil just never got that hot to require a 50 grade oil. Short trips means that the oil temperature never gets up to the normal operating range. It was too thick on short trips and too thick when it did get up to temperature.
我收集了一些小故事。首先，我的设计师驾驶一台大 SUV ，他过去在用美孚一号 15W-50 。在我的建议下他换了鹏斯多级机油（矿物基，非全合成，便宜） 5W-20 。 他在市区的燃油里程从 10 英里/加仑变为 13 英里/加仑。他从粘稠的全合成换为稀的矿物油，印象深的是起步加速变的更为强劲。他用车地点是在佛罗里达走走停停的城市交通，主要是短行驶，机油从未达到过需要用 50 粘度级的温度。短途意味着机油温度达不到正常温度范围。 50 粘度级在短途驾驶和启动时都太粘了。
The lower temperatures he saw with the thinner oil occurred because of reduced friction and internal drag and higher oil flow.
较低的温度用较稀的机油是为了减少内部阻力和获得更高的机油流速。
One of the members of the Ferrari Chat web site went from a 40 to a 30 grade oil in his Ferrari 355 for racing in Texas. He noticed a drop in temperature but no change in oil pressure. This may seem odd but really makes perfect sense. Since the 30 grade oil is thinner he got better flow and therefore better cooling. The oil was at a lower temperature so it was not as thin than it would have been at the previous higher temperature. Cooler engines last longer. Fact： The higher the temperature, the greater the wear，all other things being equal.
在一个法拉利俱乐部网站，他们用 40 到 30 粘度级的机油在他们的法拉利 355 里在德克萨斯跑比赛。他们注意到温度下降但机油压力并没有改变。这看上去有些奇怪但确实很有意义。自从换了稀的 30 粘度级机油，它获得了更好的流动性也因此更有了更好的冷却性。由于这个机油温度不高，所以他也不会变的很稀，它不会达到像以前那么高的温度。温度更低的发动机带来更长的寿命。事实上温度越高，磨损越大，所有东西都这样。
People say that their old car manual says to use a 10W-40 so they would never think of using a 0W-40. Again，both are the same viscosity at normal engine operating temperature. The 0W-40 just does not thicken as much after you turn off your engine. There are now several cases when manuals for older cars have been updated to reflect this. My 550 Ferrari Maranello manual said to use 5W-40 yet the 575 manual says to use the 0W-40. The engines are the same except the 575 has more BHP. It has better acceleration and more top speed. The engines have the same tolerances.
人们说他的老车手册上说要使用 10W-40 机油，所以他们从不考虑用 0W-40 。实际上两者在发动机正常温度下有着相同的粘度。 0W-40 只是在你熄火后不会变得那么粘稠。 现在很多案例反映出老的手册已经升级更新了。我的法拉利 550 Maranello 手册让使用 5W-4 0而 575 手册说让用 0W-40 。发动机是一样的，而 575 的马力更大，他有这更好的加速和极速。这发动机有着相同的耐受性。
All manufacturers I have seen are specifying OW-XX or 5W-XX oils now. Honda, Ferrari, Ford，Mercedes，Porsche, and others specify a 0 or 5W-XX oil to mention a few. These are appropriate for all engines of all ages of all levels of wear. This second number is the only thing that may change with an older, lose or worn engine. This can only be determined by experimentation. If you are using XW-50, go to a 0W-40. If your pressures are still too high go to a 0W-30 and so on.
现在我所看过所有的汽车制造商都指定 0W-XX 或 5W-XX 机油。本田，法拉利，福特，奔驰，保时捷和一些汽车制造商指定一款 0 或 5W-XX 的机油（仅举几例）。这些适合于所有发动机和所有实用程度磨损级别的车。第二个数只有当年老，烧机油和磨损的发动机时才需要改变，这个只能通过实验来确定。如果你从XW-50换成0W-40后机油压力还是很高的话，那就换成0W-30，以此类推。
When I took delivery of my 575 Maranello I drove for 500 miles then changed the oil to 0W-30 Mobil 1. There were no changes in operating pressure or temperature. Starting the engine seemed faster though. I called up FNA and was told that all new Ferrari Maranellos are delivered with 5W-30 Shell Helix Ultra. That is when I decided to try the 0W-20 Mobil 1.1 could have gone to a 10 grade oil as my pressures were still excessive while driving around town. I do not drive on the track.
当我的 575 Maranello 到手后我开了 500 英里就换成了美孚一号 0W-30 ，机油压力和温度都没有变化。启动发动机似乎更快了。我给 FNA 打电话，被告知所有新的法拉利预装的都是 5W-30 Shell Helix Ultra ，这时我决定试一下美孚一号 0W-20 。我也想试试 10 粘度级机油，因为我在城市驾驶的机油压力还是偏高。我不下赛道。
What about the break in period? For one thing you could just follow the car's manual and gradually break your engine in. Some cars like Ferrari and Lamborghini run engines and the cars for a period of time before you even take delivery. They often run up to full power. Some representatives at least from Ferrari hinted that the traditional break in period was not really needed，at least in their cars.
关于磨合期怎么做？第一步，遵照你的手册慢慢的磨合你的发动机。有些车，像法拉利和兰博基尼在交车之前都会让发动机运转一段时间。他们通常让发动全马力输出。至少从法拉利的一些描写暗示着传统的磨合期事实上是不需要的。
Most people who buy high powered cars that I have experienced will just get in there cars and step on the gas fully. They do not wait for the oil to warm up. Personally I would not mind running full BHP for short bursts during the break in period but I always fully warm up the engine first. Water / coolant warms up on just a few minutes but oils takes up to 30 minutes to get up to just the normal operating temperature of around 200 F.
大多数卖了大马力汽车的人都喜欢上车就大脚踩油门，不等机油预热，我也有过着方面经历。个人来讲，我并不在意磨合期短时间全马力爆发一下，但首先我要保证是完全预热以后的。水/冷却液预热只需要几分钟，但机油要用 30 分钟才能达到正常温度 93 度左右。
Older engines may in fact benefit from thinner oil use. Over time permanent deposits of carbon and sludge build up in the engine oil ways. It is like a clogging of arteries in humans. we are now all on blood thinners. This is an area I specifically studied while a general surgeon resident at Chapel Hill.
老的发动机事实上会受益于稀的机油。随着时间推移，长年的积炭和油泥在发动机油道形成，就像人的动脉堵塞一样。我们现在都希望血液更稀。这个领域我与一个住在 Chapel Hill 普通外科医生特殊学习过。
Thinner oils, and specifically synthetic products are better. Some people say their engines were “designed” to run on mineral based lubricates. I have not seen anything to support this theory. The synthetic of the same viscosity as the mineral oil you are now using will be an improvement. If you go from a mineral to an even thinner synthetic you may be better off still. The pressures go up in many older engines because of this “clogging” of the arteries. Most think this is good but it is really a lessening of flow and therefore accelerates engine wear even further.
稀的机油和特定的全合成产品都好。有些人说他的发动机被设计成用矿物油的。我还没见过有支持这个的理论依据。你改用矿物油同样标号的全合成就是一种升级。如果你从矿物油换到更稀的全合成可能会更好。一些老的发动机的机油压力上升是因为油道堵塞。很多人认为机油压力上升是好事，但其实是在减少流速，反而会加快发动机的磨损。
For those engines with excessive varnish and carbon buildup the engine oil additives of the detergent type may be of benefit. On the other hand you could just use a thin synthetic oil and change it every 200 miles for a while and end up with an even cleaner engine. With everything working properly you may actually need a thicker oil if that engine is overly worn. The thicker oil would be a disaster however, if the arteries were narrowed from deposits.
形成了过多油泥和积炭的发动机使用含有清洁成分的添加剂的机油会有好处的。另一方法，你可以只使用稀的全合成机油每 200 英里以后更换，一段时间后发动机就清洁了。如果你的发动机已经过度磨损但其它一切正常，你可以换偏粘一些的机油，不过如果主油道因堵塞而狭窄，粘的机油将会是一场灾难。
[ 本帖最后由 狮行皓月 于 2014-5-27 21:28 编辑 ]

Remember, the only difference between a 0W-40 and a 10W-40 is that the 0W-40 thickens less after you turn off your engine. It is still too thick in the morning at startup but not as thick as the 10W-40. Yet，they are still too thick to use until they both warm up to operating temperature at which point they have the save viscosity，around 13 to 14. Remember that the 0W-30, 10W-30 and straight 30 grade oils all have a viscosity of around 10 at normal engine operating temperatures. They all thicken when you turn off your engine. The 10W-30 will thicken the most.
请记住，0W-40 与 10W-40 唯一的不同就是 0W-40 在熄火后比 10W-40 粘度低，虽说第二天早上冷启动时的粘度也比发动机最适粘度高，但不像10W-40那么粘，直到预热到正常温度点后，粘度才达到正常，大约 13 到 14 cS 。记住，0W-30 ，10W-30 和单级 30 粘度的所有机油在正常发动机工作温度时粘度大约都为 10 cS 左右，在熄火后他们都会变粘，其中 10W-30 最粘。
There is one more thing. A 20 grade oil is not half as thick as a 40 grade oil. The real scale is more like the oils having an absolute thickness of 108 and 114. Now it can be seen that the 40 grade oil is only around 10 percent thicker than the 20 grade oil. The difference is not that much at operation but at startup the difference is significant. Pressure / flow dynamics go along with this 10 percent figure. A 30 grade oil should be thought of as having an absolute viscosity of 110 and a 50 grade oil has an absolute viscosity of 120. I am talking about the viscosity at operating temperatures.
有一件事，20 粘度级机油并不比 40 粘度级机油稀一半。真实比率更像是绝对粘度分别为 108 和 114 ，现在可以看出，40 粘度级机油只比 20 粘度级的粘 10% 左右。在发动机工况温度下差别并不大，但在冷启动时就完全不一样了。压力和流速都是根据这 10% 而来的，30 粘度级机油绝对粘度 110 而 50 粘度级为 120 ，这里所说的粘度是发动机正常工作温度。
I thought everyone knew that 90 percent of engine wear occurs during the startup period because oil is just too thick. Some think it is good to have a thicker oil for startup since the parts shrink when cold and would otherwise “rattle.” Sure, your piston diameter will shrink on cooling but so will the diameter of your bore. The net result is about the same clearance hot and cold. This is not true for your valves. They lengthen when extremely hot. In the Murcielago they use shims instead of self adjusting valve tappets. You need to put a millimeter of clearance there so that after expansion the valve will not be held partly open when it is supposed to be closed.
众所周知，90% 的发动机磨损发生在冷启动期间，就因为机油太粘。但有些人认为粘在冷启动时是好事，因为零件热胀冷缩，稀的会有很大噪音。没错，活塞遇冷收缩，但缸径也一样会收缩，算下来冷热间隙是一样的。这对气门来说也是不对的。在极热时会变长。在 Murcielago 里他们使用垫片代替自适应气门挺杆。你需要一毫米的间隙一遍膨胀后气门不会部分开启（当假设被关闭时）。
If it were true that thicker oils were needed at startup then the manufacturers would not be requesting oils that thicken less on cooling. They would just specify that one should use a straight 30 or 40 grade oil. Instead, over time, they have been specifying thinner and thinner oils.
如果在冷启动时需要粘的机油是真的，手册就不会要求低温粘度了。他们直接指定一款单级机油 30 或 40 粘度就行了。取而代之的是，随着时间的推移，他们指定的机油越来越稀了。
The manufacturers know what parts shrink or expand and the clearance changes that result. You do not have to worry about this. If it was that easy to design engines we would all be making them.
制造商了解什么零件收缩什么零件膨胀随之而来的间隙改变带来的结果都很清楚，你不必为之担心。如果设计发动机这么简单的话我们都能制造它了。
I would like to go back to the worry that oil falls off the parts when a car is stored or sees long periods of inactivity. For the first oil change in my 575 Maranello I drained the Shell and put in 0W-30 Mobil 1. This was at a few hundred miles on the odometer. I drove the car home from work，put it on the lift and drained the transaxle and engine oils. I also opened and drained the oil cooler and took off every line that is in the oil system. I wanted to get every speck of the Shell oil out of there. For optimal results you are not supposed to mix synthetic oils of different brands.
我们回到担心长时间停车不开机油从零件表面流走这个问题。首先我的 575Maranello 首保放了原车壳牌机油加入了美孚一号 0W-30 。那时里程表仅跑了几百英里。我下班回家，把车开上架机，放掉发动机和变速箱油，并且打开放掉了油冷中的油，拆下油路系统所有线路。我希望从这里找到壳牌机油的每个瑕疵，为了达到最佳效果，假定不混入不同品牌的全合成机油。
The system takes 12 quarts with a “normal” oil change but took 15 quarts for this change. It all took about an hour. I then started the engine to check for leaks. The multitude of mechanical engine noises that followed nearly broke my eardrums for about 10 long seconds. Then it was suddenly very quiet. You could hear a pin drop. There was certainly the most possible amount of surface oil on all the internal parts as the engine was only off for an hour. But it was not until the oil circuit primed，filled, then sent flow into all the parts that any lubrication was occurring. Hence all oil filters that are manufacturer certified have back flow limiters to keep the oil filter full even with the engine off.
这个系统正常情况需要 12 夸脱的机油但我们换入了 15 夸脱。这一切大约花了一小时 的时间。之后我启动发动机检查渗漏，近乎震破我耳膜的各种发动机机械噪音大约持续 10 秒后突然变得非常安静，甚至可以听到针落地的声音。可以肯定的是发动机内部零件表面机油流回仅需要1小时。机油循环初始化，涌入油道，之后流送到所有零件，直到所有润滑生效。因此，所有油滤清器制造商都保证有回流限制，确保即使是发动机熄火后滤清器也是满的。
Here is an interesting tidbit of information. A 75W-90 gear oil has the same viscosity as a 10W-40 engine oil at 212 and 302 F. Once again, those numbers on that oil can are misleading and certainly add to the confusion I see among automotive enthusiasts. At 75 F gear oils are much thicker than motor oils. There are no start up issues so pour point depressants are not added that minimize the thickening with cooling in gear oils.
有趣的花絮信息，75W-90 的齿轮油与 10W-40 机油在 100 度和 150 度粘度相同。这些油上的数字使人误解，给汽车爱好者们增加迷惑。在 24 度时齿轮油比机油粘的多。由于没有启动问题，倾点抑制剂（减少遇冷变稠）不在齿轮油中添加。
[ 本帖最后由 狮行皓月 于 2014-5-27 21:30 编辑 ]

Motor Oil 109
Chapter nine. Let's start over.
第九章。重新开始。
We have seen that 0W-30, 5W-30, 10W-30 and straight 30 grade oils all have the exact same viscosity at 212 and 302 F. What about startup viscosities? Do 0W-20, 0W-30，and 0W-40 all have the same viscosity at a 75 F startup. The answer is no. The SAE J300 standard allows for this discrepancy. Here are some examples:
我们知道了，0W-30 ，5W-30 ，10W-30 和纯 30 粘度级机油在 100 度和 150 度时粘度相同。那么冷启动时粘度呢？难道 0W-20 ，0W-30 和 0W-40 在冷启动 24 度时粘度也相同吗？答案是否定的，SAE J300 标准允许它有相差。来看几个例子：
..Viscosity at 75 F startup..     ..24度冷启动粘度..
...0W-20..…0W-30.....0W-40
...40............50...........60
The numbers are not exact but they show clearly that the “0” represents different startup viscosities. This is unlike the 0W-30，5W-30, 10W-30 and straight 30 grade oils that all have the exact same viscosity in a hot engine = 10 cS.
这些数字不是十分精确，但能清晰的展现出所谓的这个 “0” 在冷启动时粘度的差异， 不像 0W-30 ，5W-30 ，10W-30 和纯 30 粘度级机油在热的发动机中有着相同的粘度= 10 cS 。
I would like to comment on the following statements made by a knowledgeable automotive enthusiast:
下面我想评论一下一个知识渊博的汽车爱好者的陈述：
“Pressure and flow are tied together with viscosity，but none have anything to do with lubrication. Lubrication is a property of the fluid, not the force. The oil pump would pump water just as well, but it would offer no real lubrication. If we double the pressure, we double the flow. If you decrease the viscosity to a lighter oil，you increase flow at a loss of pressure. High flow helps to carry away more heat. High pressure helps to keep metal parts like the bearings out of contact with each other (scuffing).”
“机油压力与流速跟粘度紧密联系在一起，但对润滑不起任何作用。润滑是液体的属性，而不是力量。即使是水机油泵也能很好的泵送，如果我们给它提供双倍的压力和双倍的流速，它也不能提供实际润滑。如果你降低机油的粘度，你在油压降低的同时会获得更快的流速。机油流速高有助于带走更多的热量。高机油压力有助于保持金属零件间不相互接触（磨损）。”
Here is one example. Take an air conditioner closed bearing compressor for your home's A/C unit. Put a nipple on the bearing at one end of the shaft. Now pressurize the bearing. It will do nothing extra to reduce wear, nothing.
举个例子，找个家用空调接近压缩机轴承的地方，拿一个短节放在轴承一侧的杆上，向轴承施加压力，并不会额外的减少磨损。
I give you the following example to help visualize what is happening with motor oil. This assumes the oil has no internal resistance. In actuality doubling the pressure will not double the flow but will be slightly less. And thicker oils have more resistance than thinner oils for all situations. But simplified we get the following:
下面这个例子更形象的告诉你关于机油发生了什么。假设机油没有内在阻力。事实上双倍的压力不会得到双倍的流速，但只会少一点点。在任何情况下，粘机油的阻力都要比稀的大，但简单的我们得到如下：
For a 30 grade oil at operating temperature:     以一个 30 粘度级机油在运转温度下：
RPM....Pressure....Flow     转数.....机油压力.....流速
1,000...20 PSI.......1
2,000...40 PSI.......2
3,000...80 PSI.......4
8,000...160 PSI.....8 The maximum flow because of the oil pop off valve at 90 PSI will be 5
                              最大流速由于泄压阀弹开，在 90 PSI 时流速为 5
（翻译到这里我解释一下，在泄压阀未启动之前，机油压力随转数上升而上升，当机油压力达到泄压阀开启力度时，也就是上升到 90 PSI 时，机油压力就不再随转数上升而上升了，无论转数到多少，通过泄压阀的开启，机油压力始终就保持着 90 PSI ，由于压力不变流速也恒定在 5 这个数值上了）
For a 30 grade oil at operating temperature     以一个 30 粘度级机油在运转温度下
and a higher output oil pump:     高输出机油泵：
RPM........Pressure......Flow     转数.…机油压力..流速
1,000……30 PSI..........1.5
2,000……60 PSI.…......3
4,000.......120 PSI........6 The maximum flow because of the oil pop off valve at 90 PSI will be 5
                                     最大流速由于泄压阀弹开，在 90 PSI 时流速为 5
8,000.......240 PSI........12
If we stick with the same grade oil and increase the oil pump output we will increase the pressure and the oil flow too. If we double the oil pump output we will double the pressure and we will double the oil flow (in an ideal system). But we are always limited by the oil relief valve:
如果使用同样粘度级的机油并且增加机油泵的输出，机油压力和机油流速也随之增加。双倍的机油泵输出会得到双倍的机油压力和双倍的机油流速（理想状态下）。但我们经常会受到机油泄压阀的限制。
RPM.....Pressure......Flow     转数....机油压力....流速
1,000......40 PSI........2
2,000......80 PSI........4
4,000....160 PSI........8 The maximum flow because of the oil pop off valve at 90 PSI will be 5
                                  最大流速由于泄压阀弹开，在 90 PSI 时流速为 5
8,000….320 PSI.......16
Let us compare a 40 grade oil at operating temperature:
让我们对比运转温度下 40 粘度级机油：
The oil is thicker, has more internal resistance and therefore requires more pressure to get the same flow (baseline engine).
机油越粘，内部阻力越大，因此需要更大的机油压力才能达到相同的流速。
RPM.....Pressure.....Flow     转数.....机油压力.....流速
1,000……30 PSI.....1
2,000……60 PSI.....2
4,000.....120 PSI.....4 The maximum flow because of the oil pop off valve at 90 PSI will be 3
                                最大流速由于泄压阀弹开，在 90 PSI 时流速为 3
8,000.....240 PSI.....8
For a 40 grade oil at operating temperature     40 粘度级在运转温度下
and a higher output oil pump:     高输出机油泵：
RPM.....Pressure.....Flow     转数.....机油压力.....流速
1,000......45 PSI.........1.5
2,000......90 PSI.........3 The maximum flow because of the oil pop off valve at 90 PSI will be 3
                                    最大流速由于泄压阀弹开，在 90 PSI 时流速为 3
4,000....180 PSI..........6
8,000....360 PSI.........12
For a 40 grade oil at operating temperature     40 粘度级在运转温度下
with the original pressures:     原始机油压力：
RPM.....Pressure.....Flow     转数.....机油压力.....流速
1,000....20 PSI.........0.5
2,000....40 PSI.........1
4,000....80 PSI.........2
8,000...160 PSI........4 The maximum flow because of the oil pop off valve at 90 PSI will be 3
                                  最大流速由于泄压阀弹开，在 90 PSI 时流速为 3
Increasing the pressure while using the same oil will increase the oil flow but increasing the pressure by increasing the oil thickness will result in less flow. It takes more pressure to move a thicker oil. When you go to a thicker oil the pressure goes up because of the increased resistance, and therefore reduction of flow. Because the pressure is higher sooner, the relief valve cuts in sooner. Flow will actually be less when the RPM is up and the flow is needed the most.
同样的机油增加压力会增加机油流速，但增加压力又增加机油粘度结果是降低流速。让更粘的机油流动需要更大的机油压力。当你换了粘的机油，压力会随之增高，因为增加了阻力，因此减少了流速。由于压力迅速升高，泄压阀瞬间开启，当转数上升流速事实上更慢，而流速才是最需要的。
There is more to these graphs but I will continue with the next chapter.
下一章还有更多这样的图表。
Furthermore, in review, pressure does not equal lubrication. Let us look again at a single closed "lifetime lubricated" bearing. We could hook up a system to pressurize the bearing. This can actually be done. We could have the oil at ambient pressure. We could then double, triple, quadruple the pressure of the oil. The oil is non-compressible. Regardless of the pressure we would have the exact same lubrication, that of the ambient pressure lubrication.
此外，再回顾一下，压力不等于润滑。让我们再看看单一封闭的油脂润滑轴承。我们可以连接上一个系统给轴承加压。事实上这是可行的。我们可以让油在环境压力下，之后对油施加双倍，三倍，四倍的压力。油是没有可压缩性的。无论压力多少，我们获得的润滑是完全相同的，即使是周围环境压力下的润滑。
The physics of lubrication as I said earlier show a 1:1 relationship of flow to separation pressure. Lubrication itself is pressure independent. I will not go into the mathematical equations for this.
物理润滑就像我前面说的，流速与分散压力是 1:1 的关系。润滑本身与压力无关。这不是数学上精确的对等。
Even water can be used as a lubricant. This is partly because of its high surface tension. It is used in many medical devices and other systems that are under or exposed to water. It is just that water rusts metal parts making this unsuitable for automotive engines. It actually has a higher specific heat than oil. It can therefore carry away more heat than oil from bearing surfaces. In this respect water is a better lubricant than oil.
甚至水也可以当做润滑剂，这一部分是因为它有很高的表面张力。它被用于很多医疗设备和其他一些接触水的系统。仅仅是因为水会使金属生锈所以不适合用在汽车发动机中。其实水比机油有着更好的比热，这样能从轴承表面带走更多的热量。在这方面水是比机油更好的润滑剂。

Motor Oil 201
Chapter Ten，The Graduate.
第十章。获得学位
I am going to bring up the constant flow pump concept. First，it goes back to the principal that doubling the pressure of the same grade oil does not exactly double the flow but it is close. Also doubling the RPM for the same reason does not exactly double the flow but again it is close.
下面引出恒流泵这个概念。首先，回到主要的，同样粘度级机油，双倍的压力事实上不会获得双倍的流速但会接近双倍。同样，双倍的转数也不会精确的获得双倍的流速，但同样很接近。
This shows the problem best:      这个能很好的说明这个问题：
(A)    For a 30 grade oil at operating temperature：     运转温度下 30 粘度级机油：
RPM.......Pressure.....Flow     转数.....机油压力.....流速
1,000……20 PSI........1
2,000……40 PSI........2
4,000.......80 PSI........4
8,000.....160 PSI........8 The maximum flow because of the oil pop off valve at 90 PSI will be 5
                                    最大流速由于泄压阀弹开，在 90 PSI 时流速为 5
(B)    For a 30 grade oil at operating temperature     运转温度下 30 粘度级机油：
and a higher output oil pump:     高输出机油泵：
RPM.....Pressure.....Flow     转数.....机油压力.....流速
1,000......30 PSI.......1.5
2,000......60 PSI.......3
4,000....120 PSI.......6 The maximum flow because of the oil pop off valve at 90 PSI will be 5
                                  最大流速由于泄压阀弹开，在 90 PSI 时流速为 5
8,000....240 PSI.......12
If we stick with the same grade oil and increase the oil pump output we will increase the pressure and the oil flow too. If we double the oil pump output we will double the pressure and we will double the oil flow.
如果我们使用相同粘度级的机油，增加机油泵输出，会增加机油压力和机油流速。如果机油泵双倍输出，我们也将获得双倍机油压力和双倍的流速。
(C)    For a 40 grade oil at operating temperature:     运转温度下 40 粘度级机油：
The oil is thicker, has more internal resistance and therefore requires more pressure to get the same flow. Compare this with (A):
机油变粘了，有更大的内部阻力，因此需要更大的压力得到相同的流速。与(A)对比：
RPM.....Pressure.....Flow     转数.....机油压力.....流速
1,000......30 PSI.......1
2,000......60 PSI.......2
4,000....120 PSI.......4 The maximum flow because of the oil pop off valve at 90 PSI will be 3
                                  最大流速由于泄压阀弹开，在 90 PSI 时流速为 3
8,000.....240 PSI......8
(D)    For a 40 grade oil at operating temperature     运转温度下 40 粘度级机油
and a higher output oil pump:     高输出机油泵：
RPM.....Pressure.....Flow     转数.....机油压力.....流速
1,000......45 PSI....…1.5
2,000......90 PSI.......3 The maximum flow because of the oil pop off valve at 90 PSI will be 3
                                 最大流速由于泄压阀弹开，在 90 PSI 时流速为 3
4,000....180 PSI…....6
8,000....360 PSI.......12
The situations (A) and (C) are close to real life, assuming no loss in the system. This is what happens when you change the 30 grade oil to a 40 grade oil in your car:
假设系统没有损失，（A）和（C）两种情况都很接近实际生活。这就是你从 30 粘度级机油换到 40 粘度级机油在你发动机中所发生的：
(A) For a 30 grade oil at operating temperature:     运转温度下 30 粘度级机油：
RPM.....Pressure.....Flow     转数......机油压力.....流速
1,000.....20 PSI........1
2,000.....40 PSI........2
4,000.....80 PSI........4
8,000....160 PSI.......8 The maximum flow because of the oil pop off valve at 90 PSI will be 5
                                 最大流速由于泄压阀弹开，在 90 PSI 时流速为 5
(C) For a 40 grade oil at operating temperature:     运转温度下40粘度级机油：
The oil is thicker, has more internal resistance and therefore requires more pressure to get the same flow.
机油变粘了，有更大的内部阻力，因此需要更大的压力得到相同的流速。
RPM.....Pressure.....Flow     转数.....机油压力.....流速
1,000......30 PSI.......1
2,000......60 PSI.......2
4,000....120 PSI.......4 The maximum flow because of the oil pop off valve at 90 PSI will be 3
                                 最大流速由于泄压阀弹开，在 90 PSI  时流速为 3
8,000.....240 PSI......8
At 6,000 RPM the maximum rate of flow has been reached with the thinner oil (A). When you go to 7，8 or 9,000 RPM you do not get any more flow. You only get a maximum rate of 5. The internal forces on the bearings increase but there is no additional flow of oil.
情况（A）使用稀的机油，在 6000 RPM 时机油已经达到了最高流速。当转数上升到 7，8 或 9，000 RPM 时，并不能再获得更高的流速了，你依然获得着最大的流速5。内部作用在轴承上的力量增加，但机油流速没有得到增加。
With the thicker oil you reach maximum flow at 3,000 RPM (C). Worse yet is that the maximum flow is now only 3. As we increase RPM to 4，5，6，7，8，9,000 RPM we get no additional pressure and no additional flow, no increase in lubrication.
情况（C）使用粘的机油，达到机油最大流速在 3,000 RPM 。更糟糕的是那时的最大机油流速仅有 3 。当转数上升到4，5，6，7，8，9，000 RPM 时，我们并不会得到更高的机油压力和更高流速，也不会获得额外的润滑。

Next let us look at a 20 grade oil at operating temperature. We get the same flow out of our constant volume pump but the thinner oil requires less pressure to move through the system. This even goes along with the rule that we should use an oil that gives us 10 PSI per 1,000 RPM:
下面我们看一下 20 粘度级的机油在发动机运转温度下的情况。同样的机油泵，同样的流速，稀的机油需要更低压力。这也遵循这相同的原则，我们用的机油每 1000 RPM 获得 l0 PSI 的机油压力。
(D) RPM.....Pressure.....Flow     转数.....机油压力.....流速
1,000..........10 PSI..........1
2,000..........20 PSI..........2
4,000..........40 PSI..........4
8,000..........80 PSI..........8
The maximum flow rate has not been reached. If the engine went to 9,000 RPM then the flow would be 9 at 90 PSI，our maximum pressure at pop off. The engine now has 3 times the flow rate as with the 40 grade oil at full RPM. The nozzles at the bottom of each cylinder are spraying 3 times the amount of oil lubricating and cooling this section. Everything runs cooler and the separation forces in the bearings are 3 times higher.
这个最大流速没有达到。如果发动机达到 9000 RPM ，能达到最大压力 90 PSI 流速会达到 9。这时发动机比 40 粘度级机油满转流速快 3 倍，汽缸底部的喷嘴喷出 3 倍数量的机油润滑和散热这一部分。每个零件运转的都更凉爽并且分散了轴承 3 倍的受力。
For engines that redline at 5,000 RPM they usually pop off the oil pressure at 50 to 60 PSI. For engines that go to 8-9,000 RPM the pressures max out at 90-100 PSI. You can now see that you can only get the maximum flow rate if you follow the 10 PSI I 1,000 RPM rule.
如果发动机红线在 5000 RPM 通常 50 到 60 PSI 时泄压阀开启。如果发动机红线在 8-9000 RPM ，机油压力最大输出为 90-100 PSI 。现在可以看出，你只需遵循 10 PSI / 1,000 RPM 这个规律就可以获得最大流速。
The winner: 0W-20 grade oil for my Maranello. I said earlier that I could have used a 10 grade oil. I actually only ran with 185 F oil temperatures around town and the pressures were similar to the 40 grade oil example in (C) above. This is why I also said that in the racetrack condition, with hotter，thinner (0W-20) oil， I may actually get the optimal results as in (D) above.
获胜者：对于我的 Maranello 是 0W-20 粘度级。我之前说过，我其实想用 10 粘度级的机油。实际上我在城市驾驶机油温度仅有 85 度因此机油压力相当于 40 粘度级机油如上面的（C）情况。这就是为什么我说在赛道情况，伴随着高热量，稀的（0W-20）机油会获得最佳的效果，如上面的（D）情况。
Now let us go back to the Ferrari recommended parameters in my 575 Maranello manual. It calls for 75 PSI at 6,000 RPM. The pop off pressure has not been reached. As we now increase the RPM we still get an increase in flow rate. This is what we need and this is exactly what they are recommending. We get our maximum flow at the maximum system pressure, at about the maximum engine RPM of 7,700. There is no bypassing of the oil. All oil pumped goes through the system. There is no wasted BHP pumping oil past the bypass valve back to the oil tank. It is the perfect system.
现在我们回到法拉利 575 Maranello 手册里建议的参数。它要求在 6000 RPM 时有 75 PSI 的机油压力，这时未达到泄压阀开启压力，增加机油压力也会增加流速。这是我们需要的也正是他们所建议的，在发动机最高转数 7700 RPM 时获得最大机油流速和系统最高机油压力。机油没有走旁路，所有的机油泵送到发动机系统中。机油泵的输出没有浪费，机油没有通过旁支泄压阀流回油底壳，这是完美的系统。
Finally I will compare a single, 30 grade oil, at normal (212 F) and at racetrack (302 F) temperatures:
最后对比一下 30 粘度级机油在一般情况（100 度）和在赛道情况（150 度）：
(A) For a 30 grade oil at normal (212 F) operating temperature:     30 粘度级机油在正常（100 度）运转温度：
RPM.......Pressure.....Flow     转数.....机油压力.....流速
1,000......20 PSI.........1
2,000......40 PSI.........2
4,000......80 PSI.........4
8,000....160 PSI.........8 The maximum flow because of the oil pop off valve at 90 PSI will be 5
                                   最大流速由于泄压阀弹开，在 90 PSI 时流速为 5
(E) For a 30 grade oil at elevated (302 F) operating temperature. The oil is thinner at 302 F. It requires less pressure to get the same flow:
30 粘度级机油在升高的（150度）工作温度下。机油在 150 度时会变稀。达到相同的流速它需要更小的机油压力：
RPM.......Pressure.....Flow 转数.....机油压力.....流速
1,000......10 PSI.........1
2,000......20 PSI.........2
4,000......40 PSI.........4
8,000......80 PSI.........8 The maximum flow because of the oil pop off valve at 90 PSI will be 9
                                    最大流速由于泄压阀弹开，在 90 PSI 时流速为 9
The hotter (302 F) 30 grade oil is thinner than the cooler (212 F) 30 grade oil. It has the same flow rate in the constant volume oil pump but at a lower pressure than the oil at normal operating temperature. This allows for a doubling of the flow rate at peak RPM. The thinning of oil at higher temperatures is a benefit. You get more flow, more cooling and more lubrication.
热的（150 度）30 粘度级机油比凉的（100 度）30 粘度级机油稀。达到相同的机油流速，热的机油比正常工作温度机油需要更小的压力。这样在峰值转数流速能提升一倍。 在高温下稀的机油是有好处的，可以获得更高的流速，更好的散热和更好的润滑。
The 30 grade oil at 302 F has the exact same flow rate and pressures as the 20 grade oil at 212 F. See (D) above. Therefore, use the 20 grade for around town driving and the 30 grade on the hot track. You get maximum flow at each situation.
30 粘度级机油在 150 度时与 20 粘度机油在 100 度时流速和机油压力相同。参照上面（D）情况。因此在城市驾驶使用 20 粘度级，在高热的赛道使用 30 粘度级，两种情况你会获得相同的流速。
For YOUR engine, substitute the actual flow at 1,000 RPM. If your engine puts out 1.5 liters/min. at 1,000 RPM it would put out 3 liters/min. at 2,000 RPM and 6 liters/min. at 4,000 RPM and so on. The maximum flow in (A) would be 7.5 liters/min. In situations (D) and (E) you would get a maximum of 13.5 liters/min.
对于你的发动机，替代实际流速在 1000 RPM 。如果你的发动机在 1000 RPM 时输出为 1.5 升/分钟，在 2000 RPM 时输出 3 升/分钟，在 4000 RPM 时输出 6 升/分钟，以此类推。在（A）时最大流速在 7.5 升/分钟，在情况（D）和情况（E）时会获得最大 13.5 升/分 钟的流速。
Conclusions:
总结：
The reason that multi-grade oils were developed in the first place was to address the problem of oil thickening after engine shutdown. Over the years we have been able to reduce the amount of thickening that occurs. Never-the-less there is no oil that does not thicken after you turn your engine off. This is why we have to warm up our engines before revving them up. Engine designers always pick the recommended oil based on a hot engine and hot oil. There is no issue with oil thinning as they are both matched when hot. The problem is oil thickening when the engine cools.
多级机油发展最初是解决发动机熄火后机油变粘这一问题。多年来我们在一定程度上已经能够减少机油变粘这一现象的发生。尽管如此，并不存在熄火后一点不变粘的机油。这也是为什么在加速前我们需要预热发动机。发动机设计者选择推荐的机油总是基于热的发动机和热的机油。机油变稀没有问题，因为热了以后与发动机匹配了。问题是温度没达到时机油粘度过大。
Cold engine showing very high pressures because of the thickened oil at startup:
冷的发动机表现为非常高的机油压力，因为在启动时机油粘度很高：
For a 40 grade oil at 75 F at startup:
40 粘度级机油在冷启动 24 度时：
The oil is thicker, has more internal resistance and therefore requires more pressure to get the same flow.
粘的机油内部阻力大，因此需要更大的机油压力才能达到相同的想流速。
RPM......Pressure.....Flow     转数.....机油压力.....流速
1,000......60 PSI.........1
2,000....120 PSI.........2 The maximum flow because of the oil pop off valve at 90 PSI will be 1.5
                                    最大流速由于泄压阀弹开，在 90 PSI 时流速为1.5
4,000....240 PSI.........4
8,000....480 PSI.........8
At 1,500 RPM you reach the maximum oil flow rate and if you run to 8,000 RPM it is the same rate. The flow cannot increase and it is insufficient. This is why we must wait until our oil temperature comes up to 212 F or higher. The maximum flow rate in this case will then double, up to 3. To get even more flow in our test engine you need to use a lower viscosity grade.
在 1500 RPM 达到了最高机油流速，而且即使转数达到 8000 RPM 也是这个流速，不会增加，而且这样的流速是不够的。这也是为什么要等待机油温度上升到 100 度或更高的原因。在这种情况，最高流速会增长一倍，达到 3。想获得更高的流速经过我们的测试你需要更换更低粘度的机油。
If you have absorbed and digested the information here you should be able to pick out the proper operating oil grade for your car? be it a 30，40, 50 or even 20 grade oil. I have always used oils that were a grade thinner than recommended even though many use a grade thicker than recommended. I showed evidence that the starting grade should always be 0 or 5 (0W-XX or 5W-XX for thicker oils). If you want the best protection and highest output from your motor use a synthetic based oil. The actual brand is not as critical as the viscosity. The rating must be the SL or SM rating. Change your oil every 3 一 5,000 miles and at least every spring.
如果你已经吸收和消化了这些内容，你一定有能力选出适合你驾驶风格和你汽车的机油，它可能是 30，40，50 或者甚至 20 粘度级的机油。我一直使用比建议粘度稀一个等级的机油，尽管许多人在使用比建议粘度等级更粘的。之前我已经证明过，启动粘度应该总是 0 或 5（对于粘的机油 0W-XX 或 5W-XX）。如果想得到更好的保护和更高的输出，那你应该使用全合成机油。事实上，品牌不像粘度那样需要挑剔。等级一定要 SL 或 SM 级。更换你的机油每 3-5000 英里并且至少春季要更换一次。
Final examination to follow later.
随后是最终测试。
THE END
结束
[ 本帖最后由 狮行皓月 于 2014-5-27 21:36 编辑 ]

Motor Oil Midterm Examination
机油期中考试
Answer questions without looking back. This is a closed book exam. Base your answers on the information provided in these past chapters.
回答问题不要回顾文章。这是闭卷考试。你的回答基于前面几章提供的信息。
1- At normal operating temperature, 212 F，a straight 30 grade oil has a viscosity of how many centiStokes?
在正常工作温度，100 度，30 粘度级机油的粘度是多少厘司（cS ）？
A- 3
B- 6
C- 10
D- 20
E- 30
2- While racing at 95 F，mid-summer in Florida，which of these synthetic oils gives the best protection at 302 F oil temperature?
盛夏的佛罗里达气温 35 度，在这种情况下跑比赛，哪种机油在 150 度的油温下能提供最好的保护？
A- 0W-40
B- 5W-40
C -10W-40
D- Straight 40 grade     纯40粘度级（单级机油）
E- They are all exactly the same     以上答案者都相同
3- While starting up your car at 75 F，mid-winter in Florida, what is the approximate viscosity of a straight 10 (ten) grade motor oil?
在盛夏的佛罗里达，启动汽车时温度为 24 度，哪个粘度最接近纯 10 粘度级（单级）机油在这样温度时的粘度？
A- 3 cS
B- 6 cS
C- 10 cS
D- 20 cS
E- 30 cS or higher     30 cS 或更高
4- The biggest problem with mineral based motor oils long term use is:
长期使用矿物油最大的问题是：
A- Thinning     变稀
B- Thickening     变粘
C- Loss of VI (viscosity index) improvers     消耗粘度指数改进剤
D- Both A and C     A 和 C
E- None of the above is correct     以上都不对
5- Which of the following mineral based motor oils are still too thick at a 75 F startup temperature?
哪个矿物油在 24 度启动时是过于粘稠的？
A- 20 grade 20     粘度级
B- 10 grade 10     粘度级
C- 5 grade 5     粘度级
D- All of the above     以上所有
E- None are too thick     没有过于粘稠的

Answers to the Oil Midterm Exam
I feel these were all difficult questions. You would be doing well to get 3 correct.
我认为这些题都很有难度，能答对3道就是好样的。
1- At normal operating temperature, 212 F，a straight 30 grade oil has a viscosity of how many centiStokes?
在正常工作温度，100度，30粘度级机油的粘度是多少厘司（cS) ？
A- 3
B- 6
C- 10
D- 20
E- 30
The correct answer is C- 10 cS.
正确答案是 C- 10 cS。
2- While racing at 95 F? mid-summer in Florida, which of these synthetic oils gives the best protection at 302 F oil temperature?
盛夏的佛罗里达气温 35 度，在这种情况下跑比赛，哪种机油在 150 度的油温下能提供最好的保护？
A- 0W-40
B- 5W-40
C -10W-40
D- Straight 40 grade     纯40粘度级（单级机油）
E- They are all exactly the same     以上答案者都相同
The correct answer is E- They are all exactly the same.
正确答案是 E- 以上答案都相同。
3- While starting up your car at 75 F，mid-winter in Florida, what is the approximate viscosity of a straight 10 (ten) grade motor oil?
在盛夏的佛罗里达，启动汽车时温度为 24 度，哪个粘度最接近纯 10 粘度级（单级）机油在这样温度时的粘度？
A- 3 cS
B- 6 cS
C- 10 cS
D- 20 cS
E- 30 cS or higher     30 cS 或更高
The correct answer is E- 30 cS or higher.
正确答案是 E- 30 cS 或更高。
4- The biggest problem with mineral based motor oils with long tern use is:
长期使用矿物油最大的问题是：
A- Thinning     变稀
B- Thickening     变粘
C- Loss of VI (viscosity index) improvers     消耗粘度指数改进剂
D- Both A and     C A 和 C
E- None of the above is correct     以上者口不对
The correct answer is B- Thickening.
正确答案是 B-变粘。
5- Which of the following mineral based motor oils are still too thick at a 75 F startup temperature?
哪个矿物油在 24 度启动时是过于粘稠的？
A- 20 grade     20粘度级
B- 10 grade     10 粘度级
C- 5 grade     5粘度级
D- All of the above     以上所有
E- None are too thick     没有过于粘稠的
The correct answer is D— All of the above.
正确答案是 D- 以上所有。

Motor Oil Final Examination
机油期末考试
Answer questions without looking back. This is a closed book exam. Base your answers on the information provided in these past chapters.
回答问题不要回顾文章。这是闭卷考试。你的回答基于前面几章提供的信息。
1- While starting up your car at 75 F? mid-winter in Florida, which of these synthetic oils provides the least startup resistance, minimal battery and starter motor load?
在冬季中旬的佛罗里达，当启动发动机时气温 24 度，哪一种全合成机油启动时有最小的阻力，最少的电池消耗和最低的起动机马达负载？
A- 0W-20
B- 0W-30
C- 0W-40
D- 0W-50
E- They are all exactly the same     以上答案者口相同
2- While vacationing in Orlando，it is 104 F mid-summer in Florida. The rental car company put a straight mineral based 30 grade oil in their car because they wanted the operating temperature viscosity to be at 10 cS. What will be the approximate viscosity of the oil when you start up your engine now? (Closest answer)
在盛夏的佛罗里达州奥兰多市度假，出租车公司在他们车里使用单级 30 粘度级矿物机 油，因为他们希望工作温度粘度在 10 cS 左右。当他们冷启动时气温 40 度，哪个答案 最接近此时的机油粘度？（最接近的答案）
A- 10 cS
B- 20 cS
C- 30 cS
D- 100 cS
E- 400 cS
3- While vacationing in Florida you are able to race your car at the Sebring track. At an oil temperature of 302 F what is the approximate difference in viscosity between a 20 and 40 grade oil. (Pick the closest number)
当你在佛罗里达度假时，驾驶你的车在西布林赛道。机油温度在 150 度左右。哪个答案最接近 20 粘度级和 40 粘度级机油粘度相差数值？（选最接近的数）
A- 1
B- 10
C- 20
D- 40
E- 400
4- Assume there are no losses in the system and your oil pump is truly volume based. Also assume there is no cut off pressure valve and you are using a 40 grade motor oil. If at 1,000 RPM your pressure is 30 and your pump output is 1 (one), what will the pressure and output be at redline, 8,000 RPM?
假设系统没有损失，并且基于机油泵真实容积。同时假设没有机油泄压阀。使用 40 粘度级机油，如果在 1000 RPM 时机油压力是 30 ,机油泵输出为 1 ，那么在红线 8000 RPM 时的机油压力和输出是多少？
A- 240 PSI，flow = 8
B- 180 PSI，flow = 8
C- 240 PSI，flow = 4
D- 180 PSI，flow = 4
E- 120 PSI，flow = 8
5- Water can be used as a lubricant.
水可以作为一种润滑剂
A- True     对
B- False     错
6- If you increase the pressure in a bearing, all other things being constant, the force of separation between the parts increases.
如果增加轴承上的机油压力，其他保持不变，在零件间的分隔力会增加。
A- True     对
B- False     错
7- The best grade oil for racing any Ferrari or Lamborghini is a 40 grade multi-grade synthetic oil like Mobil One 0W-40.
最适合法拉利或兰博基尼跑比赛的机油粘度是 40 粘度级多级全合成机油，如美孚一号 0W-40。
A- True     对
B- False     错
8－ For my Maranello 575 the 0W-20 grade Mobil 1 oil was actually too thick for my driving conditions.
对于我 Maranello 575 的驾驶环境，0W-20 的美孚一号事实上太粘了。
A- True     对
B- False     错
9- The major problem with engine oil is that it thins with increasing temperature.
关于机油的主要问题是随着温度升高而变稀。
A- True     对
B- False     错
10- Your 1993 sports car manual states to use an API / SAE SH rated 10W-40 mineral based motor oil. Your engine has only 1,550 miles on the odometer. On your next oil change it would be better to use a SM rated 0W-40 synthetic oil.
你的 1993 年跑车手册规定使用一款 API / SAE SH 级别 10W-40 的矿物油。里程表显示仅仅跑了 1550 英里。你再换机油应该换更好的 SM 级 0W-40 全合成机油。
A- True     对
B- False     错
11- According to SAE J300 a 30 grade oil has a viscosity of between 9.3 and 12.4 centiStokes at operating temperature (212 F).
根据 SAE J300 ， 一款 30 粘度级机油在工作温度 100 度时，粘度应在 9.3 到 12.4 厘司（cS）之间。
A- True     对
B- False     错
12- In my list of recommended oils what did I list as the best mineral based motor oil in the 50 grade class?
在下列机油中，哪个是 50 粘度级里我推荐的最好的矿物油？
A- Pennzoil multi-grade 20W-50
B- Castrol GTX 15W-50
C- Red Line 10W-50
D- Valvoline Durablend 0W-50
E- No oil was recommended     没有推荐的机油
13- You are running 5W-40 Shell Helix Ultra fully synthetic motor oil in your Mercedes Benz. You are in a K-Mart shopping center and checked your oil and it is 1 1/2 quarts low. You will need to add one can of oil. Which of the following is the best choice.
你的奔驰里使用着 5W-40 Shell Helix Ultra 全合成机油。当你到 K-Mart 商店时发现车内缺了 1.5 夸脱，你需要添加一部分机油。下面哪种是最佳的选择。
A- Mobil 1 - 0W-40
B- Pennzoil Synthetic (全合成）5W-40
C- Red Line Synthetic 5W-40
D- Castrol Syntec 0W-30
E- Shell mineral based (矿物基）10W-40
14- Motor oils that are labeled “for racing only” should not be used for everyday driving because:
标着“for racing only”仅用于比赛的机油不适合日常驾驶因为：
A- They do not have detergents     它们不含清净分散剂
B- They may have harmful levels of some additives     它们肯能含有有害成分的添加剂（对环境有害）
C- They are generally unrated, there is no SJ? SL or SM approval     它们通常没有等级，没有SJ，SL或SM认证
D- You would have to take your engine apart and clean it periodically     你可能不得不定期将发动机拆解清洗它
E- All of the above     以上所有
15- ASTM stands for:
ASTM代表：
A- Automotive Standards and Test Methods     汽车标准和试验方法
B- Automotive Society for Tooling and Machining     汽车模具及加工协会
C- American Society for Testing and Materials     美国测试和材料协会
D- American Standards Trade and Manufacturing     美国标准贸易和制造业
E- Society for American Standard Testing Methods     美国标准协会测试方法
16- If your engine is running too hot at higher RPM one thing you can try to bring the temperature down is to use a thinner oil.
如果你的发动机在高转时过热，想解决这一问题可以使用稀的机油。
A- True     对
B- False     错
17- Oil with a startup thickness of 100 (at 75 F) that becomes the appropriate thickness of 10 when fully warmed up (212 F) is called a 10W-30 grade motor oil.
机油在启动时粘度是 l00 cS（在24度），通过充分预热后（100 度）粘度变为 l0 cS 这样的机油被叫做 10W-30 粘度级机油。
A- True     对
B- False     错
18- A main advantage that the synthetic has over the mineral based oil of the same grade is the ability to lubricate better at startup.
全合成机油超越矿物油主要优势在于同粘度级在启动时润滑性能更好。
A- True     对
B- False     错
19- In ASTM D 4485 3.1.4: Engine oil is defined as -- “a liquid that reduces friction and wear between moving parts within an engine, and also serves as a coolant.”
在ASTM D 4485 3.1.4中：机油被定义为--“一种在发动机运动零件间减少摩擦和磨损液体，并能提供冷却服务。”
A- True     对
B- False     错
20- I am (single best answer):
我是（最佳答案，单选）：
A- Surgeon     外科医生
B- Biochemist     生物化学家
C-‘Halfass mechanic     半个修理工
D- Absurdly interested in motor oils     机油爱好者
E- All of the above      以上所有

Answers to the Oil Final Exam
机油期末考试
I feel these were all very difficult questions. You would be doing well to get 10 correct.
我感觉这些问题是非常有难度的。能答对10道就是优秀了。
1- While starting up your car at 75 F，mid-winter in Florida, which of these synthetic oils provides the least startup resistance, minimal battery and starter motor load?
在冬季中旬的佛罗里达，当启动发动机时气温24度，哪一种全合成机油启动时有最小的阻力，最少的电池消耗和最低的起动机马达负载？
A- 0W-20
B- 0W-30
C- 0W-40
D- 0W-50
E- They are all exactly the same     以上答案者口相同
The correct answer is A- 0W-20.
正确答案是 A- 0W-20。
2- While vacationing in Orlando，it is 104 F mid-summer in Florida. The rental car company put a straight mineral based 30 grade oil in their car because they wanted the operating temperature viscosity to be at 10 cS. What will be the approximate viscosity of the oil when you start up your engine now?
在盛夏的佛罗里达州奥兰多市度假，出租车公司在他们车里使用单级30粘度级矿物机油，因为他们希望工作温度粘度在 10 cS 左右。当他们冷启动时气温 40 度，哪个答案最接近此时的机油粘度？（最接近的答案）
A- 10 cS B- 20 cS C- 30 cS
D- 100 cS
E- 400 cS
The correct answer is D- 100 cS.
正确答案是 D- 100 cS。
3- While vacationing in Florida you are able to race your car at the Sebring track. At an oil temperature of 302 F what is the approximate difference in viscosity between a 20 and 40 grade oil. Pick the closest number.
当你在佛罗里达度假时，驾驶你的车在西布林赛道。机油温度在 150 度左右。哪个答案最接近 20 粘度级和 40 粘度级机油粘度相差数值？（选最接近的数）
A- 1
B- 10
C- 20
D- 40
E- 400
The correct answer is A- 1.
正确答案是 A- 1。
4- Assume there are no losses in the system and your oil pump is truly volume based. Also assume there is no cut off pressure valve and you are using a 40 grade motor oil. If at 1,000 RPM your pressure is 30 and your pump output is 1 (one), what will the pressure and output be at redline, 8,000 RPM?
假设系统没有损失，并且基于机油泵真是容积。同时假设没有机油泄压阀。使用 40 粘度级机油，如果在 1000 RPM 时机油压力是 30 ，机油泵输出为 1 ，那么在红线 8000 RPM  时的机油压力和输出是多少？
A- 240 PSI, flow = 8
B- 180 PSI, flow = 8
C- 240 PSI, flow = 4
D- 180 PSI, flow = 4
E- 120 PSI, flow = 8
The correct answer is A- 240 PSI，flow = 8.
正确答案是 A- 240 PSI，flow = 8。
5- Water can be used as a lubricant.
水可以作为一种润滑剂。
A- True
B- False
The correct answer is A- True.
正确答案是 A- 对。
6- If you increase the pressure in a bearing, all other things being constant, the force of separation between the parts increases.
如果增加轴承上的机油压力，其他保持不变，在零件间的分隔力会增加。
A- True
B- False
The correct answer is B- False.
正确答案是 B- 错。
7- The best grade oil for racing any Ferrari or Lamborghini is a 40 grade multi-grade synthetic oil like Mobil One 0W-40.
最适合法拉利或兰博基尼跑比赛的机油粘度是 40 粘度级多级全合成机油，如美孚一号 0W-40 。
A- True
B- False
The correct answer is B- False. It can best be determined by driving the car with one type of oil and follow the pressures and temperatures of your oil.
正确答案是 B- 错。哪种类型油最好，取决于驾驶的汽车油压和温度。
8- For my Maranello 575 the 0W-20 grade Mobil 1 oil was actually too thick for my driving conditions.
对于我 Maranello 575 的驾驶环境，0W-20 的美孚一号事实上太粘了。
A- True
B- False
The correct answer is A- True.
正确答案是 A- 对。
9- The major problem with engine oil is that it thins with increasing temperature.
关于机油的主要问题是随着温度升高而变稀。
A- True
B- False
The correct answer is B- False. The problem is thickening when the engine is turned off. With long term use the problem is also thickening. Engine oils grades are matched at operating temperature. It is after the engine cools that viscosities are an issue.
正确答案是 B- 错。问题是发动机熄火后机油变粘。经过长期的使用问题依然是机油变粘。机油粘度等级是跟发动机工作温度匹配的。当发动机冷却了之后粘度就是问题了。
10- Your 1993 sports car manual states to use an API / SAE SH rated 10W-40 mineral based motor oil. Your engine has only 1,550 miles on the odometer. On your next oil change it would be better to use a SM rated 0W-40 synthetic oil.
你的 1993 年跑车手册规定使用一款 API / SAE SH 级别 10W-40 的矿物油。里程表显示仅仅跑了 1550 英里。你再换机油应该换更好的 SM 级 0W-40 全合成机油。
A- True
B- False
The correct answer is A- True. Although it may actually be preferential to use a modern 0W-30 grade oil.
正确答案是 A- 对。尽管事实上优先使用一款现代的 0W-30 粘度级机油
11- According to SAE J300 a 0W-30 and a straight 30 grade oil must have a viscosity of between 9.3 and 12.4 centiStokes at operating temperature (212 F).
根据 SAE J300 ，一款 30 粘度级机油在工作温度 100 度时，粘度应在 9.3 到 12.4 厘 司（cS）之间。
A- True
B- False
The correct answer is A- True.
正确答案是 A- 对。
12- In my list of recommended oils what did I list as the best mineral based motor oil in the 50 grade class?
在下列机油中，哪个是50粘度级里我推荐的最好的矿物油？
A- Pennzoil multi-grade 20W-50
B- Castrol GTX 20W-50
C- Red Line 15W-50
D — Valvoline Durablend 20W-50
E- No oil was recommended     没有推荐的机油
The correct answer is E- No oil was recommended. They all are too thick at startup for daily use.
正确答案是 E- 没有推荐的机油。他们在日常冷启动时都太粘了。
13- You are running 5W-40 Shell Helix Ultra fully synthetic motor oil in your Mercedes Benz. You are in a K-Mart shopping center and checked your oil and it is 1 1/2 quarts low. You will need to add one can of oil now. Which of the following is the best choice.
你的奔驰里使用着 5W-40 Shell Helix Ultra 全合成机油。当你到 K-Mart 商店时发现车内缺了 1.5 夸脱，你需要添加一部分机油。下面哪种是最佳的选择。
A- Mobil 1 - 0W-40
B- Pennzoil Synthetic 5W-40
C- Red Line Synthetic 5W-40
D — Castrol Syntec 0W-30
E- Shell mineral based 10W-40
The correct answer is E- Shell mineral based 10W-40. You can mix any SM rated oil in there but this is my first choice based on my research.
正确答案是 E- Shell mineral based 10W-40 。你可以混入任何 SM 级别机油，但我首选的是基于我研究过的。
14- Motor oils that are labeled “for racing only” should not be used for everyday driving because:
标着“for racing only”仅用于比赛的机油不适合日常驾驶因为：
A- They do not have detergents     它们不含清净分散剂
B- They may have harmful levels of some additives     它们肯能含有有害成分的添加剂（对环境有害）
C- They are generally unrated, there is no SJ, SL or SM approval     它们通常没有等级，没有SJ，SL或SM认证
D- You would have to take your engine apart and clean it periodically     你可能不得不定期将发动机拆解清洗它
E- All of the above     以上所有
The correct answer is E- All of the above.
正确答案是 E- 以上所有。
15- ASTM stands for:
ASTM代表：
A- Automotive Standards and Test Methods
B- Automotive Society for Tooling and Machining
C- American Society for Testing and Materials
D- American Standards Trade and Manufacturing
E- Society for American Standard Testing Methods
The correct answer is C- American Society for Testing and Materials.
正确答案是 C- 美国测试和材料协会。
16- If your engine is running too hot at higher RPM one thing you can try to bring the temperature down is to use a thinner oil.
如果你的发动机在高转时过热，想解决这一问题可以使用稀的机油。
A- True
B- False
The correct answer is A- True.
正确答案是 A- 对。
17- Oil with a startup thickness of 100 (at 75 F) that becomes the appropriate thickness of 10 when fully warmed up (212 F) is called a 10W-30 grade motor oil.
机油在启动时粘度是 l00 cS（在24度），通过充分预热后（100 度）粘度变为 10 cS ， 这样的机油被叫做 10W-30 粘度级机油。
A- True B- False
The correct answer is A- True.
正确答案是 A- 对。
18- A main advantage that the synthetic has over the mineral based oil of the same grade is the ability to lubricate better at startup.
全合成机油超越矿物油主要优势在于同粘度级在启动时润滑性能更好。
A- True
B- False
The correct answer is A- True.
正确答案是 A- 对。
19- In ASTM D 4485 3.1.4: Engine oil is defined as -- “a liquid that reduces friction and wear between moving parts within an engine, and also serves as acoolant.”
在 ASTM D 4485 3.1.4 中：机油被定义为--“一种在发动机运动零件间减少摩擦和磨损液体，并能提供冷却服务。”
A- True
B- False
The correct answer is A- True.
正确答案是 A- 对。
20- I am (single best answer)
我是（最佳答案，单选）：
A- Surgeon     外科医生
B- Biochemist     生物化学家
C- 'Halfass mechanic     半个修理工
D- Absurdly interested in motor oils     机油爱好者
E- All of above     以上所有
The correct answer is E- All of the above.
正确答案是 E- 以上所有。

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