Standards for applying grease to bearings

Is this method by the maintenance supervisor good? Are there any improper maintenance practices?

You can’t add more. Excessive carbonization will occur, affecting the bearing’s lifespan; in severe cases, it may lead to improper shutdowns

This behavior is wrong; adding too much oil might prevent you from being able to drive

I’ve learned it! Such phenomena are quite common, especially among older mechanics. A manifestation of laziness and irresponsibility.

Of course, there is a specified amount of butter to be added. But Gado isn’t that great either. After starting, the excess butter is squeezed out along the oil seal.

We fill it up here as well; we need to change that in the future.

The masters said that it shouldn’t be filled to the top, as doing so will result in poor lubrication and cooling effects!

I’d like to let everyone know the results of this maintenance check: the motor has burned out! Hahaha

But I think there are two possible reasons for the motor to get damaged. 1) There is a problem with the motor’s protection system; too much bearing oil can cause the motor to lock up over time, and it’s a problem that the electrical protection mechanisms do not function properly. 2) If we consider the theory that heat causes the grease to soften and flow onto the motor stator, leading to inter-winding short circuits and thus motor damage, then the quality issue of the motor coils themselves is the main cause

Actually, adding too much isn’t a serious problem, because the butter will be squeezed out after driving

Ten Misconceptions About the Use of Lubricants. Misconceptions regarding lubricant use: The lubricants used include three types – engine oil, gear oil, and grease – which play various important roles in operations such as reducing friction, providing sealing, cooling, cleaning, and preventing rust. However, some drivers have various misconceptions regarding the use of lubricants. For example, the tendency to choose a higher viscosity rather than a lower one, and to use more lubricant rather than less, are both unscientific approaches. Misconception 1: The higher the viscosity of the lubricant, the better. Some drivers believe that oil with a higher viscosity results in higher pressure, which can reduce wear. Lubricating oil must have sufficient viscosity to form an oil film between moving parts at various operating temperatures, thereby preventing wear on the contact surfaces between those parts. However, the viscosity of the lubricating oil must not be so high as to affect engine starting, and it is required that friction under continuous operation be minimized. Using lubricant with excessive viscosity increases wear on machine components, because: (1) The high viscosity of the lubricant results in slow flow; oil rises slowly, and although the oil pressure is high, the amount of lubricant that reaches the friction surfaces is limited, preventing timely replenishment of those surfaces. Especially during startup at low temperatures, since the oil has poor fluidity at such low temperatures and cannot reach the very small friction gaps in time, wear is more likely to occur. ⑵High-viscosity lubricants increase mechanical friction losses; due to their high viscosity, the friction force between the rubbing surfaces of the machinery increases, making it harder to start the machine, leading to higher power losses and increased fuel consumption. If a lubricant with lower viscosity is used, the frictional losses within the oil can be reduced, without an increase in wear of the machine components. According to tests, reducing the viscosity of engine oil by one grade results in a fuel savings rate of 1%–3% for the engine. ⑶If the lubricating oil has a high viscosity, its circulation speed is slow, resulting in poor cooling and heat dissipation effects, which can easily cause the engine to overheat. ⑷Due to the slow circulation speed of the lubricating oil, it passes through the lubricating oil filter fewer times, making it difficult to remove worn metal particles, carbon particles, and dust from the friction surfaces in a timely manner. Therefore, do not use engine lubricants with too high a viscosity, and never assume that the higher the viscosity, the better. Under the condition of ensuring lubrication, and depending on the temperature range during use, a lubricant with lower viscosity should be used to maintain lubrication. However, for engines that are already severely worn with larger clearances, an oil with a slightly higher viscosity can be appropriately chosen. Myth 2: It’s better to add more fuel than less. The dangers of insufficient engine lubricant are well known to everyone. As a result, some car owners are worried that running out of oil could damage the engine components, and they believe that it’s better to use more lubricant than less. For this reason, they often don’t fill the tank with the required amount of oil, causing the level of lubricant to exceed the standard. In fact, having too much lubricating oil poses many hazards: (1) As the engine runs, the crankshaft stirs the oil, causing the oil foam to deteriorate and increasing the resistance to the rotation of the crankshaft. As a result, not only does it increase fuel consumption, but it also reduces the engine’s power, leads to an increase in oil temperature, and causes oil leaks from the seals. Some engine overheating problems are caused by adding too much fuel. Therefore, the amount of lubricating oil added must be moderate. ⑵Increased oil consumption is caused by more oil leaking from the cylinder walls into the combustion chamber for combustion. Some engine oil burning faults are caused by adding too much oil. ⑶It accelerates the formation of carbon deposits in the combustion chamber, making the engine prone to detonation. Therefore, the idea that it’s better to have more engine oil than less is a misconception; generally, the oil level should be kept slightly below the mark on the dipstick, as having too much oil can have the opposite effect. Myth 3: When maintaining and repairing vehicle hub bearings, some drivers fill the interior of the hub with grease, believing that the more grease there is, the better. Filling the hub cavity with grease will cause most of the grease to spill into the hub’s interior; instead of reaching the bearings, this will lead to various negative consequences. One of these is an increase in the operating resistance of the bearings ； Second is the impact on bearing heat dissipation ； Third, grease that melts due to high temperatures may seep into the brake drum, causing the vehicle’s brakes to fail. Therefore, \"hubless lubrication\" should be employed, that is, only grease needs to be applied to the bearings, without filling the cavity with grease; this ensures good lubrication while also saving a large amount of grease. Myth 4: Blindly trusting foreign brands and expensive oils. Lubricants from internationally renowned brands are certainly of better quality, but this doesn’t mean that all foreign brands produce high-quality lubricants; moreover, their costs are usually higher. In fact, the oil products of some major domestic brands, such as Kunlun, Uni-President, Hengyun, and Great Wall, also have guaranteed quality; it is best to choose oils in accordance with the requirements of the car manufacturer. Many multi-grade oils, such as those suitable for both gasoline and diesel engines or for use in winter and summer, generally cost much more than single-grade oils. However, their quality level is not necessarily higher; they simply offer greater versatility. Myth 5: Craving cheap prices. Some drivers, in an attempt to save money, often focus only on the price of fuel and the immediate maintenance costs, ignoring the higher repair expenses that will arise in the future. When selecting lubricant, the quality grade should be chosen based on the speed, load level, and type of gear transmission. High-quality lubricants have superior performance parameters, which enables them to significantly extend the service life of machinery and the oil change interval, thereby reducing maintenance costs. Especially when motor vehicles are operating under heavy load for extended periods on poor road conditions, it is advisable to choose a lubricant of a quality grade one higher than that specified in the user manual. Myth 6: Believing that blackened engine oil means it has deteriorated, and that oil that does not turn black is good quality oil. Engine oil operates under harsh high-temperature conditions, where it is prone to oxidation and degradation, producing acidic substances that accumulate as polymer deposits, thereby compromising the lubrication effect. Furthermore, the combustion exhaust gases entering the crankcase can also cause the engine oil to oxidize and deteriorate. Therefore, after being used for a certain period of time, engine oil usually turns black and deteriorates, losing its proper lubricating properties. However, as the quality of lubricants continues to improve, darkening of the oil does not necessarily mean that the oil has deteriorated; many of the dark substances in the oil are high-molecular-weight deposits and carbon deposits from within the engine. This is because the cleaning dispersants added to the engine oil can wash away these substances, causing the deposits on the machine parts to disperse in the oil. Blackening of the engine oil helps to maintain cleanliness inside the machine; therefore, darkened oil does not necessarily mean that the oil has deteriorated. Myth 7: Mixing engine lubricants. For various lubricants, the base oils are essentially the same; the difference lies only in the types and quantities of additives included. Although oils from different manufacturers can achieve the same performance, their formulations are generally different. Lubricants with different types of additives cannot be mixed, as this may cause chemical reactions between the additives in the oil, thereby compromising the effectiveness of the lubricant. In accordance with the requirements in the instructions, it is necessary to carefully compare the manufacturer, type, and grade of the oil, and select an appropriate grade and usage level; it is not permissible to use it blindly or in combination with other oils. Myth 8: Mixing old and new lubricants. New lubricants and old lubricants, even if they are of the same type, must not be mixed together. This is because old grease contains large amounts of organic acids and impurities, and mixing it with new grease will accelerate its oxidation and deterioration. Therefore, when changing the lubricant, it is essential to clean the old lubricant from the components before applying new lubricant. Myth 9: Applying butter when installing the cylinder gasket. Some mechanics like to apply a layer of butter to the cylinder gasket when installing it, believing that this can improve the engine’s sealing. What they don’t realize is that doing so is not only useless but also harmful. If butter is applied to the cylinder gasket, when the cylinder head bolts are tightened, some of the butter will be forced into the cylinder passages and oil passages. The butter that remains between the gasket layers, under the influence of high temperatures during engine operation, will partially flow into the cylinders and burn there, while another portion will turn into carbon deposits that accumulate on the surface where the cylinder block meets the cylinder head. Under high pressure and temperature, this can easily cause the cylinder gasket to be punctured or burned through, resulting in engine leakage. Butter that enters the water channels adheres to the inner walls of these channels, hindering heat dissipation and leading to poor cooling of the engine as well as high temperatures. Therefore, do not apply butter when installing the cylinder gasket. Myth 10: Lubricant must be applied to all bearings, and any moving parts need to be oiled for maintenance. With the advancement of automotive technology, many bearings now use maintenance-free double-sealed bearings, such as the split bearings found in certain vehicle models. These bearings feature double-sided sealing; many mechanics damage this sealing during vehicle maintenance, clean it and apply ordinary grease, or simply modify them to have a structure that allows butter to be applied. These bearings, having been maintained, often suffer accelerated damage. There are also some components, such as the imported brake clearance adjustment arm; due to the very small internal gaps, once the existing lubrication is disrupted, the added oil cannot reach the working surfaces, which leads to damage from lack of lubrication, or movement restrictions caused by particles in the oil.

For bearings operating at normal speeds, the amount to be added should be half of the volume; for low-speed bearings, more can be added, but not to full capacity. You can add more after it has been running for a few days.

Add Gado grease. . It has the opposite effect. . . The bearing will instead heat up. . . Recharging should follow a regular schedule. . Use less. . Be diligent. . .

Open-type bearings come out of the factory with the lubricant filled to capacity, while maintenance-free bearings are shipped without a full amount of lubricant. When installing open-type bearings, the lubricant can be filled up to the capacity on the bearings themselves, but in the bearing housing it should be filled to no more than half capacity