The topic is probably as old as the world, but to find something that clearly explains the dilemmas of many, this is already a problem, most think that it is better to replace it on a warm engine (this is how more than one instruction gives) because, as they think, more will flow, others think that it will be less flowing in a relatively short time (15 minutes) because the engine that has been working a moment ago has oil splashed all over the engine and it must take a long time for it to drain out in the same amount as the drained cold oil. Of course, let's not dwell on engines that are cold to -25 degrees celsius. and oil that has not been changed for 10 years and is so thick that the pan needs to be unscrewed, consider engines in which the oil is changed every 10,000 or 2 years. Every sentimental owner of some kind of wets care about the flow of this oil as much as possible, some even go so far as to unscrew the bowl together, of course, with the filter, others prefer to rinse the engine with cheap oil and fill it with the right one, others after draining the cold oil start the car for a few seconds - it is not about the fact that the car is started, but the oil pump is moved, then an additional 0.5l of dirty oil flows, after such a procedure, after driving 200 km, the oil is still so clean that it is difficult to see it on the dipstick, I am writing about gasoline here because in deliaslach oil it gets dark in the first seconds of firing, no matter how the oil is changed, although the latter method is moronic for many because they believe that the engine is damaged (working for a few seconds without oil) this engine works in total for more than 5 seconds because it has to draw the oil, for many it does not matter much because the engine always runs dry when starting. More than one changes the oil, draining it, whether it is hot or cold, and floods it, without even replacing the oil filter, does not pay attention to it whether there is something left in the engine or not, after changing the oil in accordance with the instructions (on a hot engine), the durability of the engine does not change, but maybe succumbs?
WHAT IS THE OPINION OF OTHERS AND I AM NOT INTERESTED BY THOSE WHO HAVE NEVER DRAINED OIL AND HAVE NO MORE CONCEPT OF MECHANICS ONLY OF THOSE WHO CAN CREATE SOMETHING AND KNOW ABOUT THINGS. Maybe some links to interesting articles on the topic would be here?
I am dealing with this, and I don't think it matters. The engine is never dry fired because there is a film of oil on all moving rubbing surfaces. Running an engine without oil is stupid to me, because what you get is "pay" when starting after replacement, before the pump is full and all oiling channels, the situation may not be dramatic, but definitely worse than without such innovations.
The oil pump is able to (I do not know whether to push but) to give the oil back without sucking in a new dose, certainly not all of the oil, but about 200 ml (a glass). This amount may cause the old oil to mix with the new one, giving a 'start after mixing' 'brown oil.
I have not read more nonsense for a long time. Something like this could only be written by a young theorist with a head full of ideas from the same Internet theorists as himself. But to the point. It's not even about running the engine dry anymore. The greatest foolishness is to empty the pump of oil which, thanks to its viscosity, seals it. After sucking in air and losing the oil film between the gears of the pump and its housing, the pump loses the ability to suck in fresh oil itself. Then such an individual pours in fresh oil, starts the engine and waits until the oil pressure lamp goes out. And it does not go out, so the bladder may help. And this is how the engine gets through the lack of pressure on the bearings. Modern oils have a high TBN number, which characterizes the cleaning properties of the oil. So, in a modern engine with modern oil change in time, there is no need for any additional oil change procedures. You simply drain the hot oil from the sump, you must replace the oil filter, fill in the new oil to the correct level. Then you start the engine, the pump fills the filter and the oil pressure lamp goes out, you turn off the ignition. You wait a while and refill the oil to the correct level because the oil ran out after the lubrication system was pumped up. Ready. Some engines, e.g. TDI, have a filter cartridge placed in a special housing. When changing, the old oil can be sucked out of the housing before inserting the new cartridge. Instead of combining, it's better to just change the oil more often. Instead of, for example, in the LL system at about 30,000 km, we change the oil with a filter every 15,000 km. It certainly won't hurt, quite the opposite.
A friend must be an expert on this and that there are a lot of such people in pl. It's probably not worth fucking with a thorough oil change, it's better to do it more often, but when you buy a used car, you don't have much to choose from, the argument that some SHELLS get in the ass after draining the oil from the pump is rather exaggeratedly written, the oil is sucked in without any serious problems (a good pump for passenger cars, not trucks) because the pump is not dry as pepper after such draining, the time it takes to deliver the oil to the pans is minimal, I suspect that within a few seconds the pans are also not dry as pepper, so although I can be completely wrong . It should not matter when the pump is emptied 1 or 3 times, after all, the bushings are not so loaded at start-up, but I admit that the air sucked in can slow down, and even significantly the possibility of sucking a new dose of oil, especially in cars with high mileage. I raised the topic because I have no experience and one day I listened to some people discussing it and as I supposed to have some idea about the engine, I was asked to contribute and unfortunately due to the lack of this knowledge, I could only philosophize. Most mechanics will tell you that the oil is changed on a warm engine, but if you ask why on a warm one and not on a cold one, they have one and only argument because the oil is thinner, and my question is whether cold oil is not the same with -20 degrees Celsius only +15 is enough thick that it flows slower? no, it does not run off slower, in addition, the most polluted part of the oil runs off, unlike the hot engine.
The topic may not be worth reading, but there is nowhere like this.
The pump is not as dry as pepper if you drain the old oil and pour new oil without running the engine. It gets dry when you start rotating its drive quickly without adding any oil to the suction side of the pump. In my professional life, I have diagnosed and repaired several different engines with damaged main and connecting rod bearings due to air in the oil pump for various reasons. In both car and motorcycle engines, the dry pump will not suck in the oil itself or it will take a long time, and this is an indisputable fact. Remember that the pump is always installed above the oil level in the oil pan. You haven't heard about seized shafts in moto engines after running on rubber (one wheel)? It only takes a few seconds, e.g. in Coffees, for it to rub on the 3rd cup. For this, stunters remake the place where the dragon is attached to the oil, create special pockets in the oil pan, or pour more than the recommended oil, so that the dragon never emerges from the oil. Bleeding the lubrication system may require, for example, unscrewing the oil filter and removing the spark plugs. We turn the shaft with the starter until oil appears in the filter socket. Then tighten the filter and turn the starter until the indicator light goes out. Thanks to the unscrewed spark plugs, the starter turns the shaft very quickly without the load of normal engine operation. In another engine, in order to suck in oil after a long stay in the warehouse, it was necessary to pump oil from the outside into the oil main after removing the oil pressure sensor. It was only this procedure that allowed the pump to be flooded with oil and sucked through it from the sump - one of many examples that I have encountered personally. So I am surprised by your approach to the subject, but everyone does as they see fit.
When the car is burned before replacing it, it is better hot, it will drain faster. However, if it stands on the canal overnight, it is cold - that's just logic. Will you drive and warm it up? And it turns out to be the same.
NO IT IS the same thing, I think we are aiming for it that it does not matter whether I drain the oil on a cold or warm engine, and it is not true that engine oil should ALWAYS be drained on a warm engine, it should burn, although a warm engine is not always hot. And this question again, because my colleague does not read from the beginning whether the warm oil from the engine that has just been put out will drain faster than the cold oil in the same amount at the same time !! ????? e.g. 15 min.
When you flood some 20w50 crap from the 80s and try to change it in winter, I am not surprised that you need to warm it, because this jelly, even in light winter, does not want to run off at all. In the age of synthetics, such a topic should end up in the basket long ago.
Mechanics know perfectly well what to change oil for hot, not cold. For interesting pseudo mechanics, I will explain: - The used oil in the engine is a colloidal solution. Modern oils, thanks to the strong dispersion properties of soot particles, sludge, sludge, varnish, etc., allow you to keep the engine perfectly clean. Everything that is not needed in the engine remains on the oil filter, and smaller particles are dissolved in the oil. Contrary to appearances, carbon particles in the form of soot and graphite have a friction-reducing effect, so they are not harmful to a certain amount. However, if the oil is standing still, all the particles that make up the solution in the oil begin to precipitate and settle in the oil pan, oil channels, etc. As the oil is heated while the engine is running, these fine contaminants again form a solution in the oil. By draining hot oil, we get rid of the maximum amount of impurities contained in the old oil. When draining the cold oil, e.g. after a night in the garage, you drain the oil with less impurities, because some of them precipitated and remained in the engine. Then you add new oil, start the engine, and some of the old dirt flows in the new oil. For those who want to deepen the topic, I recommend reading the literature, for example FUELS, OLEJE, LUBARY Janina Michałowska. The book is old, but many of the issues discussed in it are still relevant.
'' Modern oils, thanks to the strong dispersion properties of soot particles, sludge, sludge, varnish, etc., allow you to keep the engine perfectly clean ''
Unscrew the valve cover in the engine in which the oil was regularly changed, with not high mileage - what IDEAL dispersion properties can you talk about then ??? A PURE THEORY that has little to do with reality, even writing about gasoline engines.
How long does it take for these particles to start precipitating from the oil 3h, 8h, 24h or several weeks or even months, or immediately after cooling down, ???????
'' By draining the cold oil, e.g. after a night in the garage, you drain the oil with less dirt because some of it precipitated out and was left in the engine ''
So what has this part of the pollutants evaporated and deposited in the channels and tubules? rather, it is only in the sump and it is in the place where it contacts it that there is a possibility that these impurities will remain.
Dear reader, with the greatest respect for you, but you present some old, as you admit, book and some theory, maybe partly logical, in the description you write about modern oils, does it make sense ??
I had the opportunity to change the oil a few times and maybe I did it incorrectly, but I drained it on a cold engine and not because I could burn myself on a warm one, but because I was convinced that it is better.
I had a Punto with a 1100 MPI engine, after draining the oil and replacing the oil filter, I started pouring a new one without tightening the screw in the bowl, only when I noticed how the new oil was coming out, I turned the drain screw. After this order, I had clean oil for a long time and it was difficult to see it on the dipstick, and it was really because of the large number of kilometers traveled. around 500. Other colleagues, despite a different engine, but also with a low mileage, did not enjoy such a clean oil, I suspect that the procedure of draining the oil on a warm engine is not as accurate as on a cold engine - of course it is impossible to make too many such conclusions right away this can be influenced by various factors.
I almost had a heart attack, what did you 'eat' today?
I change the oil every 10kkm and so up to 5000km it is clean and transparent. And at 10,000 km after the finger test it is still clear. I never put oil in black goo. Moreover, by unscrewing the oil plug, all aluminum parts are clean and shiny, not smeared with black carbon deposits.
Exchange only on hot, ......... what he writes for, after all, it's the level of the toilet in Hades.
The topic may be stupid, but the current arguments do not reach me, and this is because arrogance appears here.
Be consistent in what you write and read, and if you can't do it for elementary school, as at the beginning I wrote to express something, have your imagination! just what does that have to do with this?
'' Well, I read a lot of information on just changing the oil, in the automotive press, so they probably know what they are writing and that's where they pointed out that treating a hot engine with cold oil can damage the head ... Of course, it is known that this does not always happen, because they constantly replace yes, oil in service stations and nothing ... But when you read it carefully, you can notice many statements like "they changed my oil, and after leaving the site after a few kilometers, the engine suddenly stopped and went out" and in many cases the expert opinions showed damage heads ... But it is like washing car windows in winter with warm water - they say they break, I also did it several times this winter and ... the windows of the entire Applause One thing is for sure - changing the oil yourself and waiting for the engine to cool down is the best Applause solution ''
'' A few such "exchanges" and at the bottom of the bowl you will have a nice swamp - see how much oil they suck with this method in relation to how much they should - 1/3 is left, and that's the worst sludge. Pouring cold oil into a hot engine causes surface stresses in parts that are rapidly cooled down and their thermal deformation, mainly the camshaft (because it is most often directly under the filler) '' '' When I add oil to a cold engine (Fiat 1, oL fire) and even after 30 minutes I go, the oil pan seal is blown out. In this case, the oil clogs the pneumothorax. by pneumothorax without clogging it (pneumothorax channels and oil drainage from the camshaft pass through the engine block). The engine cools down quickly and 15 minutes after turning the engine off, its temperature is much lower. '' '' It all depends on the engine and its correct (well-thought-out) design ... I have been pouring oil for 3 years only when the engine (sixteen-valve) is completely cold and there have never been problems with clogging pneumothorax ... it had a much lower temperature ... besides, as I wrote in websites or workshops, they do not wait even these 15 minutes, they only pour cold oil directly into the hot engine ... '' " First, the vacuum sump emptying method may not be as accurate as the traditional method, but very little oil remains, around 30-40g. This amount is much less than 1/3 and has no significant effect on the condition of the fresh oil. More than once I have emptied the bowl in this way to then disassemble it in order to, for example, replace the gasket so my words may be credible.
Under the second, in a regularly serviced car, you will not find any sludge in the sump - the oil is homogeneous. The pump head is located just above the bottom of the pan, so the oil circulation in the system is very good. Any impurities remain in the filter
Third, thermal deformation of the camshaft is impossible. The shafts, like the crankshafts, are made of hardened, low-alloy, heat-resistant steels. At most, the camshaft may break. It is not possible to bend, deform. When pouring cold oil, usually elements made of less thermally resistant materials - mainly aluminum heads '' '' It is true with this cracking of the cylinder heads due to the addition of oil on a hot engine, for example in the BMW M20 engines. As for sucking oil - there are engines in which you will suck more oil than you can drain with a plug, e.g. matiz. When I change the oil in my own, I usually unscrew the cap and filter in the evening and pour oil in the morning. '' '' It is worth knowing that the damage to the shaft is usually the result of an earlier damage to the engine or, what happens most often, of improper condition of the oil. The working conditions of the camshaft are much heavier than the situation when we pour cold oil into a warm engine
Dude, I have been on the forum for a short time and I noticed that you enjoy a lot of authority here. Reading the archive I must honestly admit that your knowledge is great and you have helped many times. And a lot of respect. But it also irritates me that you try to fill the gaps in this knowledge with your imagination. Please keep that in mind. '' '' Hello gentlemen. I will not talk about the oil suction, but if you write so wisely, I would like to note something: 1. The shafts are rather made of high-alloy steels, structural steels are low-alloyed ... 2. With increasing temperature, the dimensions of the material change, but with this type of elements the expansion is negligible, otherwise the engine would wear out quickly 3. The shafts at issue have such a high hardness and low plasticity that they break most frequently and deformation is rare 4. Shape change due to poor storage is a fact because there is creep, but the camshaft in the sun ?! How many years would he have to lie and in what heat? Well, unless it's a cast iron ... ''
does 10% old oil mixed with new oil have better lubricating properties than the whole new oil anyone can find something about it?
as it turns out, some interesting topics have already been discussed