Engine oil change interval (period): engine hours and mileage

Any motorist wants to know what is the most optimal engine oil change interval depending on mileage, engine hours, days or season. Regulations based on these criteria are calculated differently. You also need to pay attention to the condition of the engine, and also rely on factory recommendations, especially if the car is still under warranty. After the end of the warranty period, you have to rely not only on the advice of the experts, but also take into account the operating conditions, driving style, viscosity of the engine oil and other criteria on which the condition of the oil and its replacement interval depend.

When you shouldn’t follow factory regulations

Most automakers recommend changing engine oil every 10-15 thousand km or once a year. At the same time, you should not always rely only on the factory regulations, because it is much more correct to focus on engine hours and conditions of use. Prolonged operation of the engine in traffic jams and at high speeds, as a rule, leads to overheating and deterioration of the oil quality ahead of time.

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Method number 5. Change the oil according to the calendar

For whom this method is best suited, we already wrote at the beginning of the article, so we will not repeat ourselves.

Of course, one cannot discount external factors affecting oil consumption.

Here are the most important:

1. The degree of engine wear causes increased lubricating oil consumption

2. Engine type. Diesel and rotary engines consume more oil. Degree of load (turbocharge, compression ratio, temperature).

3. Fuel type. For alcohol and diesel fuel, oil changes are needed more often, but for propane and methane, on the contrary, less frequently. These recommendations were made both after research by US and are given directly by some automakers.

4. Ambient temperature. The rate of heat transfer directly depends on the temperature difference. At high external temperatures, heat exchange conditions sharply deteriorate, and the degradation of the lubricating properties of the oil accelerates. Oddly enough, this is not the biggest problem. High ambient temperatures, such as in the desert, promote oxidation, increasing volatility and additive performance.

5. Antifreeze. Low quality coolant leads to engine overheating and also accelerated oil degradation.

6. Oil filter. Poor quality filters or replacing them too rarely also shortens the life of the oil.

And we must remember that unreasonably increasing replacement intervals reduces the reliability of engine operation.

The best motor oil. does it exist?

Of course, under such conditions, intensive degradation of the active additives contained in the oil occurs. Moreover, the situation is aggravated during short city trips, when the oil does not have time to warm up to operating temperature, and this leads to the formation of wear particles. Constant driving in traffic light traffic jams, sudden changes in throttle, frequent starts in frosty weather, off-road driving or on the highway at high speed - in such conditions, you definitely shouldn’t rely on the factory’s recommendations, but it’s better to cut the interval in half. That is, in this situation, the safest oil change period should not exceed 8 thousand km.

Nanoprotek - myths and truth about changing oil after winter and ahead of schedule

SURPRISES

The tests lasted almost six months. Believe me, we have something to show: the summary tables turned out to be so huge that they would be more suitable for a dissertation than for a journal article. Therefore, the results were separated for each sample separately. But we won’t compare oils and give out seats - that’s not the purpose of the tests. But some general conclusions are immediately apparent.

So, the first phenomenon. The viscosity of all oils during long-term idle operation up to a certain point is significantly less than during “highway driving”. Why? We believe that when the engine is idling (and this is not as stable a mode as at operating, higher speeds), the passage of exhaust gases into the crankcase increases, and with them, unburned fuel mixing with oil. This is confirmed by the fact that the flash point drops at the same time, and this is one of the main signs of the presence of fuel in the oil.

The drop in viscosity is 0.4...0.6 cSt. Is it a lot or a little? For the bulk of oils, this does not mean crossing the lower limit of the viscosity class and is about 5...6% of the average level. But with the “twenties” the percentage will be greater. However, we will try to verify these assumptions during the following examinations.

Further - more interesting. Starting from a certain operating time in idling mode (70...100 engine hours), the viscosity begins to increase sharply, ahead of the “highway” cycle indicator - the oil ages before our eyes. Why? Most likely due to prolonged contact with products of incomplete combustion that have a certain acidity. Here's the result of driving through traffic jams! Idling is affected by poor ventilation of the combustion chamber due to the closed throttle valve, and low turbulence of the air-fuel mixture due to the relatively slow movement of the piston. Hence the poor combustion rate. But the passage of gases into the crankcase, as already mentioned above, is maximum.

This dynamics is not the same for different oils. It is less pronounced for ZIC XQ, Shell Helix, Motul X-cess and much more noticeable for Esso Ultron and BP Visco. We look at the results of the previous test - and on the “highway” the picture of changes in viscosity for the same oils was similar.

By the way, it seems to us that the situation is aggravated by elevated oil temperatures in the sump during idle mode. We also wrote about the dangers of volumetric overheating earlier (ZR, 2013 No. 3), and here we see new confirmation of this hypothesis. We did not reach complete polymerization in any experiment, but for some oils the dynamics of viscosity growth was quite unpleasant.

Check the condition of the oil often!

Severe conditions under which the oil is changed every 7-8 thousand km

1. Short trips around the city or rural paths. Under such conditions, the engine does not have time to warm up to operating temperature, and this leads to a deterioration in the effectiveness of oil additives responsible for neutralizing fuel combustion products. In other words, due to a cold engine, these additives work more slowly and cannot cope with the formation of dirt deposits, which subsequently accumulate on the engine crankcase and the oil itself. As a result, circulation and lubricant quality deteriorate. In addition, during short trips, condensation forms, which then turns into water and enters the oil. This is how oil ages
2. In addition to oil, in severe conditions the quality of the fuel deteriorates faster, which never completely burns, and during the combustion process ash, tar, sulfur, soot and other combustion products are formed, and then deposits appear in the form of soot, sludge, varnish, etc. Of course, the quality of fuel is negatively affected not only by difficult conditions, but also by low-quality motor oil or its untimely replacement. Even the most expensive synthetics will sooner or later become unusable and will no longer be able to remove all deposits from the engine.
3. Driving in dusty areas or on icy roads treated with special chemicals. In dusty conditions, you should not always rely on the oil filter, which is not able to capture all the dust particles that enter the engine. It is possible that one day the air hose will crack and unfiltered air will enter the engine. The ingress of dust particles into the cylinder-piston group causes increased wear of internal combustion engine parts and a sharp deterioration in the anti-wear properties of engine oil.
4. Constant use in traffic jams or frequent trips at low speeds without any load, as well as long periods of idling - all this also falls under difficult conditions. The oil is used faster during sudden acceleration and braking, and at idle the oil pressure decreases. Because of this, the fluid flows slowly into the engine and does not lubricate the parts well. Therefore, frequent trips on dirt roads are extremely undesirable, because in such conditions the engine is quite overloaded and the oil flows slowly. At idle, the engine is also poorly washed with oil, which leads to rings sticking and deposits accumulating
5. Traveling in extreme conditions with high or low temperatures. In the hot season, the engine heats up faster along with the oil, which is not able to “envelop” the parts with a durable oil film. Due to the heat, the film becomes thin and the coefficient of friction increases, as a result the film breaks and the motor parts are left without any protection. This is especially dangerous when towing heavy trailers at high suburban speeds. In addition, due to high air temperatures, the oxidation process of internal combustion engine components is accelerated and the service life of the oil is reduced. At low temperatures, there are often cases when the driver unsuccessfully tries to start the engine, although the fuel manages to enter the engine in a small amount, which is enough to settle on the crankcase. This fuel then enters the oil and dilutes it. The fuel subsequently burns as it should, but the oil itself is already spoiled. If you successfully start the engine, you cannot wait long for it to heat up, because long periods of idle time will not do the oil any good.
6. Operation using trailers and transporting heavy loads, frequent trips in mountainous areas. Of course, in such conditions, the oil runs out of its life much faster, and the engine wears out tens of times faster than when used sparingly. In mountainous areas, sharp ascents and descents are possible, which also negatively affect the life of the lubricant.

First, let's figure out what functions the oil performs in the engine.

The main purpose of motor oil is to create an extremely thin shock-absorbing film to separate metal components and prevent them from contacting when the parts rotate against each other.

The thickness of the oil film has its optimal value. If it becomes very thin, friction increases and the surfaces come into contact. If the film is too thick, then large friction losses occur, of course there is no wear, but the efficiency decreases due to the fact that it is more difficult for the engine to mix the thick film.

Inside the combustion chamber, the oil film acts as a sealant to close the gap between the piston rings and the cylinder wall. This very movement creates very noticeable heat.

Therefore, the second task of oil is to carry away heat and cool metal parts.

It should also clean the engine and carry dust, dirt, combustion byproducts (soot and acid) and waste oil residues to the filter. In addition, the oil must neutralize acids, protect the metal from corrosion and hold foaming components as vortex parts, driving air into them.

In general, the main functions of motor oil are:

1. Engine protection.

2. Protection of its parts from wear.

3. Prevention of corrosion.

4. Overheat protection.

5. Removing engine wear products from important areas, for example, metal shavings remaining after friction.

6. Removal of soot, carbon deposits and other fuel combustion products.

During engine operation, the oil gradually becomes unusable, becomes contaminated and loses its properties. The oil partially loses its physical properties due to stress during operation: temperature changes, stretching and compression.

In addition, foreign particles (sand, dust, dirt) get into the oil, which can damage the cylinder walls, plus carbon deposits gradually form. The concentration of soot and other unburned and partially burned fuel components increases, which contribute to the accelerated formation of deposits.

In addition to contamination, there is another factor that reduces the overall effectiveness of the oil. We are talking about oil degradation
.
Degradation manifests itself in three different ways. Oxidation products, sulfur substances or nitration products appear in the engine oil. The oil is also “saturated” with exhaust gases.

If you want the engine to faithfully serve its intended life without repairs, if you want to be sure of the reliability of your engine, there is a simple way that everyone knows - change the oil OFTEN.

You, of course, can change the oil according to the regulations established by the official dealer (for Land Rover this is usually 12,000 km), you can even arrange reruns, but in this case, pretty soon you will start having problems primarily with the USR, with the turbine, and then with the engine.

This is why the service interval is of utmost importance to prevent oil contamination or degradation.

Now comes the fun part. Why does it need to be changed more often than the official regulations.

Let's look not at the mileage, but at
how many engine hours
this or that oil is designed for:

Mineralka

(which we call semi-synthetic) -
replacement 170 engine hours
, edge - 200 engine hours

Cheap synthetics

- replacement
200 engine hours
, edge - 250 engine hours

Top synthetics

- replacement
250 engine hours
, edge - 300 engine hours

Top synthetics at PJSC

- replacement
300
engine hours, edge - 350 engine hours

What is engine hour?

Engine hour

- this time is one hour during which the engine was running.

It would seem that. That everything is simple. But not really. If you count the crankshaft revolutions, then in 1 hour of idling it will be approximately 60 thousand revolutions, in highway conditions - approximately 150 thousand. In city conditions, traffic jams - it can reach up to 200 thousand crankshaft revolutions. But it is difficult. For passenger cars, an engine hour is roughly 1 hour of operation of the crankshaft at a predetermined speed and a certain gear.

How to determine the number of engine hours?

If you have an on-board computer installed, then everything is simple with acceptable accuracy. Let's look at the formula.

P=S*M

P = Mileage

S = Average speed

M = Engine hours

On practice. after maintenance, we reset the route and drive 2-3 thousand km. and look at the average speed.

For example, 30 km/h, how much will it be in km. with an oil life of 200 operating hours?

30 * 200 = 6,000 km

Now let’s look at what you have filled in and count:

Let's say you have good synthetics. The oil must be changed after 250 operating hours.

What happens if you don't change the oil on time?

1. The engine will begin to overheat due to old oil, which poorly removes heat from rubbing parts
2. There will be an overaccumulation of wear products on the engine crankcase, which will result in a decrease in engine power and torque, as well as an increase in CO2 emissions.
3. The cleaning and anti-corrosion properties of the oil will deteriorate
4. Due to dirt deposits, the oil channels will become clogged and the engine will be susceptible to overheating.
5. It is possible for the connecting rod bearings to rotate, which quite often happens when the oil is not changed on time.
6. Due to dry friction and insufficient lubrication, parts will be subject to increased wear, and this can lead to excessive fuel consumption.
7. In the worst case, there is too high a probability of expensive engine repairs due to jamming, scuffing or failure of the turbocharger (if equipped)
8. Used oil will thicken and stop effectively lubricating and cooling engine parts, causing problems with starting in cold weather and other problems.

Consequences of overdue replacements

If one replacement is overdue, then without disassembling the engine you may not notice the consequences, and subsequent timely replacements and the use of good oil will partly correct the situation that has developed inside the internal combustion engine, but if you constantly carry out such an experiment and roll it over, then you can expect certain consequences:

• Accumulation of pollution . The oil gradually becomes contaminated with combustion products, this is clearly visible on the dipstick; it becomes black over time; in addition, additives are produced that are responsible for flushing the engine. As I wrote above, by 10,000 miles, few oils retain an acceptable alkaline number, and the acid increases. The additive package that flushes the parts is produced, and the amount of substances is reduced. That is, the oil loses its washing and dispersing properties, does not dissolve contaminants and does not retain them in itself, and all these substances calmly move through the oil channels and wholeheartedly harm all parts of the internal combustion engine, depositing on the surface.
• Parts begin to wear out . This happens for the same reason - the package of additives responsible for protecting parts from wear is produced. If you analyze the re-rolled waste, you can find a large number of waste products in it - silicon, metal, aluminum.
• Viscosity increases . The reasons are the same - accumulation of contaminants, oxidation, disruption of the polymerization of additives responsible for maintaining stable viscosity. As a result, the oil circulates worse through the system, and the engine runs dry from time to time. This can lead not only to a refusal to start when cold, but also to the engine knocking if it is already worn out and is not in the best condition. In addition, due to the increased viscosity, the oil film is thicker, which is what this leads to - I already wrote above.
• Rotating the connecting rod bearings . Too thick oil clogs the oil channel, and the thinner it is, the higher the load on the connecting rod bearings. For this reason, they overheat and turn over.
• The turbocharger (if there is one) wears out. Its rotor suffers the most. Oil waste negatively affects the compressor shaft and bearing, causing scratches and damage. Oil with accumulated contaminants clogs the channels, which can cause the compressor to jam.

How to check the oil

1. Open the hood, pull out the dipstick and wipe it with a clean rag.
2. Insert the dipstick back into the engine and remove it again
3. Using the marks on the dipstick, determine the oil level, which should be between the two marks. If the level is below the permissible level, then topping up will be required
4. Topping up is prohibited if the oil shows signs of deterioration in quality: - cloudiness, blackening - the presence of wear particles (traces of soot, drops of water, metal shavings) - viscosity has decreased and the useful properties of the oil have deteriorated

In this case, it is not necessary to top up, but to completely change the oil with preliminary flushing of the internal combustion engine.

WHAT DO WE CONTROL?

We will judge the patient’s health by changes in basic physical and chemical parameters. This is the dynamics of changes in oil viscosity at different temperatures, alkaline and acid numbers, as well as flash point. The scale is two-level, like “alive - dead”. For example, we consider dead oil the viscosity of which is outside the limits prescribed by the SAE class. In our case, the permissible viscosity range is 12.5...16.3 cSt. A drop in the base number by more than two times from the initial value is a generally accepted rejection parameter; we will also accept it as a conditional criterion for the death of the oil. Another criterion (we have not yet rejected any oil based on it) is the so-called loss of the additive package, which indicates the complete unsuitability of the oil. It is characterized by a sharp (at least threefold) decrease in the concentration of active elements in the oil - zinc, barium, phosphorus - in relation to the initial amount.

As usual, let's check the level of deposits that the oil produces during operation. To do this, let’s estimate their number and color on the side surfaces of the pistons (the so-called analogue of the EPV method). A completely white piston is zero points, an all black piston is six points. Intermediate gradations have their own scores in this interval. All this refers to the so-called high-temperature deposits. And we will evaluate the low-temperature ones quantitatively by weighing the main dirt collectors before and after the tests - the oil pump intake fungus, as well as the oil separator mesh from the valve cover. An increase in the mass of parts will indicate the “degree of sloppiness” of the oil.

The engine wear parameters after the test cycle will help evaluate changes in the protective functions of the oil when operating in the “highway” and “traffic jam” cycles. They can be determined by the content of the main wear products in the oil (for us, the indicator was the presence of iron in it), by accurately weighing the piston rings and crankshaft bearing shells before and after testing.

Mileage or engine hours: which is better to focus on?

It is generally accepted that the standard engine oil change interval is 15 thousand km. If you go by engine hours, then in this case there will be a fourfold difference with the same mileage on the highway and in city mode. This means that engine hours are more important, although everyone has long been accustomed to looking only at mileage. For example, you can take the standard interval of 15,000, at which the shelf life of the oil in city traffic jams will be 700 hours, and on the highway this figure will not exceed 200 hours.

Of course, a threefold difference is colossal, especially when it comes to the quality of the oil. As you know, oil experiences high thermal stress even at low engine load. Moreover, the situation is even worse in modern engines, which are characterized by high temperature control. There are also known problems due to insufficient crankcase cooling when the car is stopped in a traffic jam. And poor cooling reduces the life of the engine and oil.

On the highway, the engine does not always experience high load - at least this happens much less often than on the highway. At a constant speed of 100-130 km/h, the load is usually below average, the temperature and crankcase cooling are within normal limits. Of course, more powerful engines in such conditions are much less susceptible to overheating and have a high safety margin, while the oil is in the most ideal conditions.

However, as speed increases, the load on both the oil and the engine increases. This means that in a small engine there will be a sharp jump, while the oil load in more powerful engines will increase more gradually. And at very high speeds, oil operating conditions may deteriorate in both cases (regardless of engine power). To prevent this from happening, the average speed should be half the maximum. It is also not recommended to leave the engine idling for a long time.

As a result, we can come to the conclusion that it is better to navigate by engine hours. However, if we proceed from the factory regulations of 15 thousand, then the shelf life of the oil in engine hours will be from 200 to 700, depending on driving conditions. It is generally accepted that with daily city trips at an average speed of 20-25 km/h, the oil will become obsolete in 400 hours, which is equivalent to 8-10 thousand kilometers.

Method No. 3 - Determine the interval between oil changes based on fuel consumption

This is the most interesting and, for some unknown reason, the least known option. Both oil consumption and fuel consumption are essentially derivatives of the same factors. They both correlate most with the amount of work performed. And this is logical.

The task of motor oil (motor oil, engine oil) is to prevent, as far as possible, engine wear. Wear normally depends most on the amount of work performed. And the distance and time of work are only components of the work itself. And they are suitable for measuring oil degradation time only for this reason. And fuel consumption more accurately reflects the work done by the device than the previous parameters. Because the incoming gasoline (gas, diesel, alcohol) provides just that. No one needs to explain that 100 engine hours at 2000 rpm is far from the same as 100 engine hours at 6000 rpm. Moving a car weighing 2 tons over a distance of 1000 km is different from moving a one-ton car over the same distance. Switched on climate control (car air conditioning, any other electronics), system malfunctions, all this increases both the work performed and the load on the engine. And fuel consumption. And, of course, it shortens the life of motor oils. Everything is logical and even almost everything is clear... except for the most important thing. How to count? Exactly how much fuel should be consumed before the next oil change? And how can you find out the total fuel consumption? Count all refuelings and refuelings, write them down on stickers and paste them all over the cabin? Some people do just that. Someone pays with a card and, having calculated expenses for a certain period (a month or two), extrapolates the data for a longer period. Someone delegates this work to automation. Some engine hour meters actually count fuel consumption and then automatically convert them into standard engine hours. This is the easiest and most convenient way.

If for some reason you want to do the recalculation yourself, but at the same time save time, then you can take it as a rule that in today's gasoline engines, oil consumption is approximately 0.2% of fuel consumption. Turbo engines need significantly more lubrication, diesel engines even more, and rotary engines more than even diesel engines. For a more accurate calculation, you can use fuel consumption calculators from the Internet. The name of one of them is so impressive that we decided to give the name in full - “Calculator for empirical calculation of oil change intervals based on actual fuel consumption.” If you replace a calculator with an electronic computing device, oil with a lubricating fluid for an engine, and fuel with a calorific fluid for an internal combustion engine, then the name of the calculator will become so long and scary that people will begin to be afraid to count and will take your word for it. And here it is, available at the link:

https://etlib.ru/calc/oil-change-by-fuel-consumption

You are required to enter three parameters:

• Mileage recommended by the car manufacturer before changing the oil
• Fuel consumption declared by the manufacturer per 100 km
• Actual fuel consumption per 100 km

and you are given the interval to change your engine oil.

Drivers who are not intimidated by formulas can use one of the formulas for calculating the engine oil change interval, such as the Kublin formula.

Kublin's formula:

Mileage (km) = (244.38 x TBN x Vm x Vdv) / (L100 x Pls)

Vm = number of liters of oil when changing; Vdv = nameplate engine volume in cubic centimeters; L100 = fuel consumption in liters/100km; Pls = nameplate engine power in horsepower; TBN = oil base number.

It contains a key indicator for calculating fuel consumption, but the last point is the alkaline number of the oil. And this brings us to method number 4

When is a seasonal oil change needed (summer/winter)

Difficult operating conditions require more frequent engine oil changes, and here the interval can no longer be tied to either scheduled maintenance or seasonal replacement. Replacement times in such conditions can be unpredictable, and in this case, the factory schedule of 10 or 15 thousand km will have to be reduced, especially when it comes to short city trips, when the oil does not have time to reach operating temperature, which leads to the appearance of deposits. As a result, the replacement frequency has to be reduced to 8 thousand km.

Seasonal mileage difference

An annual replacement at the same time will be erroneous if the car travels 5 thousand km in the first year, and 30 thousand in the second year. In this case, you need to focus on the schedule regulated by the plant. Therefore, annual replacement is relevant only when the car does not have time to cover the regulated amount of mileage in one year.

There are two cases in which seasonal oil changes are justified. For example, this is relevant for high mileage, and in regions with sudden climate changes, the oil must be changed twice a year. In such conditions, it is better to use an all-season fluid, while highly specialized lubricants are recommended for regions with extremely low and high temperatures. For example, in winter, an oil with a lower viscosity is better to ensure more efficient engine starting. In summer, on the contrary, a more viscous oil is required, which reduces fuel consumption. In addition, seasonal oils are usually cheaper than universal ones.

It is extremely important to choose oil depending on the season

If you add summer oil in severe frost, then problems will arise with the operation of the battery and starter. At low temperatures, you should choose only “winter” oils with a viscosity from 0W to 20W. For example, the best option would be oil with a viscosity of 0W-30, which is easy to pump and is designed to operate at temperatures from minus 30 to plus 20 degrees. In addition, with such oil you will not have to warm up the engine for a long time.

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It's clear? None (!) of the gasoline tested by the company's representatives corresponds to anything - then what do you want from motor oils?

It is clear that this is nonsense. We have been checking fuel throughout the country for many years, we are quite familiar with the state of affairs, but to declare 100% of the capital’s gasoline unfit is too much. I wasn’t the only one who was surprised; a series of questions arose. First, the respected German speaker was asked how he would explain the polymerization of oil on a brand new dealer car, which was still filled with original, clearly “non-Soviet” gasoline? There was no answer. The next question is quite simple: is it safe to refuel at a gas station with a Shell sign? And was Shell gasoline included in the above-mentioned report? Again ambiguity.

The next report is based on the results of a study of spoiled oils. Everything is very interesting, but we were again hinted that the situation with ruined engines was perfectly simulated after paraffins were added to the branded oil. And if so, then there is only one recipe: improve quality control... of Russian fuel!

However, that day common sense managed to win. One of the venerable invited oil workers sarcastically asked: where is the evidence that harmful paraffins were hidden in gasoline? And a respected lady from Rosstandart CMTU directly asked whether the speaker understands what kind of queue of idle cars immediately forms on the side of the road if everything is really so bad with gasoline in Russia?

I remember that when I got to the microphone again, I reminded that during the Zarulev tests we deliberately tried to spoil the oil with frankly crappy gasoline - it didn’t work! The engine then sneezed, twitched, but worked - and no asphalt formed in the pan. It all ended with the following recommendations being given to ordinary users.

Recommendations for preventing the loss of service life of motor oils

Oil change timing. Options

Replacement timing by mileage and average speed

• 20-30 km/h – 7 thousand km
• From 60 km/h – 8-10 thousand km

Replacement periods by engine hours

• In the city - 200 engine hours
• On the highway – 300 hours

Replacement dates by season

• Twice a year - autumn or spring
• Once a year - only in spring

Replacement timing depending on engine type

• Gasoline - 12-15 thousand km
• Diesel - 7-9 thousand km

Replacement periods depending on the type of oil

• Semi-synthetics - 9-12 thousand km
• Synthetics - up to 15 thousand km

terms of Use

Under ideal conditions, the car develops a speed of 40 km/h in the city, we get 15000/40 = 375 engine hours. For a suburban highway we assume 80 km/hour, calculating 15000/80=188 engine hours.

Let's compare the experimentally obtained figure of 576 with the calculated 375, we conclude: the engine operates under difficult operating conditions, to increase its service life it is necessary to change the oil 2 times more often. Many people don’t know: engine fluid replacement is regulated and amounts to:

• 250 operating hours for ACEA E2, API CF, CF-4, CG4;
• 400 - VDS, ACEA E3;
• 600 - for VDS-2.

The service book states that under severe operating conditions, the oil is replaced every 8 thousand kilometers. Such conditions include:

• there is a significant amount of dust in the air;
• long driving at low speed;
• moving a vehicle over mountainous and hilly terrain;
• high temperature outside the car;
• use of fuel of questionable quality;
• frequent changes of gas stations;
• when towing a trailer;
• fully loaded trunk.

If it is not possible to carry out this calculation, experts recommend relying on fuel consumption. For example, a car must consume 9 liters of gasoline or diesel fuel per 100 km in the city, according to the regulations, for 15 thousand kilometers it will be 1350 liters - (15000/100)*9, the real consumption is 11 liters per 100 km, at 15 thousand km will be 1650 liters. It is necessary to change fluids at a volume of 1350 liters. This method is relative.

When answering the question: “How many engine hours should pass before replacing the engine mixture in the engine?”, consider:

1. Type of power unit. The temperature inside diesel engines is much higher than in gasoline-powered drives. The lubricant is subjected to heavy loads.
2. The engine is under load; as the load increases, the service life of the oil decreases.
3. The car drives on a country road or around the city. On the highway, the engine wears out more slowly: it works for a long time with the same load.

Change the mixture according to the engine hours traveled, do not carry out scheduled fluid changes based on the mileage of the car. Use certified products that meet the technical characteristics of the engine, use motor oil that meets the recommendations of the vehicle manufacturer.

Advice from motorists

1. To increase the replacement interval, it is necessary, if possible, to buy high-quality branded oil, which must meet all factory specifications and requirements.
2. You can use a vacuum replacement if the owner is ready to reduce the interval. But this procedure is less expensive than a complete replacement, it is performed quickly and does not require much effort.
3. You should try to change the oil on time, and for this it is recommended to do regular checks of the level and condition of the fluid. Thus, this will avoid unpredictable engine problems.
4. You should not experiment with additives and additives in the hope of increasing the replacement interval. These additives have a short-term effect, and then they enter into a chemical reaction with the oil and impair its beneficial properties. Because of this, we have to reduce the regulations
5. When changing the oil, it doesn’t hurt to check the chassis, but the most convenient way to do this is with a lift at a service station
6. As the mileage increases, the engine will consume a little more oil - within acceptable limits, and this is absolutely normal. With a mileage of over 80 thousand km, you need to check the level more often and add fluid if necessary.

What determines the frequency of replacement?

Each car manufacturer gives detailed information in its manual about when to change the oil. But this information does not always correspond to real life. Usually in the documents you can see the mileage on average from 10 to 15 thousand km, depending on the brand of the car. But in reality, these numbers are influenced by various factors.

1. Quality and type of fuel (diesel, gasoline, gas).
2. Engine displacement.
3. Type and class of oils used.
4. Brand of lubricant poured (mineral, synthetic, semi-synthetic).
5. Condition of the engine oil.
6. Full mileage.
7. Replacement method.
8. The quality of the purchased oil.
9. Mode and operating conditions.
10. Vehicle condition.

The plant’s recommendations are not taken into account in this list, since for them the frequency of replacement is a marketing ploy.

Engine size and type

A powerful motor can more easily withstand heavy loads and difficult working conditions. Therefore, the lubricant will not deteriorate too much. A car with a powerful power unit moving on the road at a speed of 120 km per hour does not put much stress on it.

Subcompact cars are usually equipped with a transmission with a low gear ratio for driving at low speeds and engine speeds. Therefore, in difficult conditions, their motors experience greater load compared to powerful engines. When the load increases, the piston group heats up more, and the volume of gases in the crankcase increases. This increases the temperature of the motor lubricant.

It’s especially difficult for “small cars” with forced 1.2-liter engines. In this case, the load is also added by the turbocharger.

Operating mode

First of all, the frequency of engine lubricant changes is affected by the operating mode of the vehicle. Without going into details of this process, there are two types of modes - urban and suburban. The question is, if the car drives around the city, its mileage will be less, and the load on the power unit will be greater. This is due to frequent downtime in traffic jams and at traffic lights with the engine running. There is not enough cooling.

If the car is used on country roads, the situation is completely different. The mileage is longer, and the engine is cooled much more efficiently. Therefore, the load on the motor and lubrication is also reduced.

It would be more correct to determine when to change the engine oil, taking into account the engine hours. This is done for agricultural and cargo equipment. For example, in a city a car will travel 10,000 km in about 400 engine hours, but the same distance outside the city will take only 100 engine hours. In addition, different operating modes must be taken into account.

It is not for nothing that driving in a big city is equated to rough terrain, as this has a detrimental effect on lubrication. The effect is especially noticeable when the oil level is below average or minimal. In addition, in hot weather there is more load on the oil due to the increased temperature of the air and the road surface.

Other factors

Additional conditions that affect the timing of engine lubricant replacement include high operating temperature. In addition, you need to take into account the characteristics of the oil, the contamination of the oil filter, the condition of the lubrication channels, compliance of the lubricant with the factory recommendations, its originality, and crankcase ventilation.

Note! The optimal time for changing the lubricant is 200-400 operating hours, not counting the maximum load.

In addition, the type of oil plays an important role - synthetic, semi-synthetic, mineral water.

Design and principle of operation of instruments for measuring engine hours

A counter helps calculate engine operating time. After a certain time has passed, it beeps or turns on a relay. The meter makes it possible to carry out timely maintenance, routine replacement of parts, and repairs. The counter continuously counts the time while it is turned on. When turned off, the countdown stops. When it is turned on again, the count starts from the extreme value, and not again. The MC counter tracks reserves. It measures the available life of the motor and controls the time of its maintenance. Using such a device, the car owner can monitor the performance of the engine. As a result, this reduces costs and minimizes downtime.

Features of hour meters and methods of their use

The counter counts seconds, minutes. When the hour ends and its value approaches 59.59, one is added to the hour, seconds and minutes start from 00.00. When the engine hour calculation reaches a critical value, a signal sounds. Thus, the device informs the owner about the need to monitor the engine condition.

Types of hour meters:

• Non-resettable. Calculates equipment operating time from one second to 9999 hours. Does not reset.
• Resetable. Counts from seconds to 9999 hours. There is a possibility of resetting.

The design and quality of the meters are different. The devices available on the market are divided into groups according to functionality:

• Electronic.
• Mechanical.
• Electromechanical.
• Digital.

A mechanical device is considered a classic device. It is made on the basis of a spring mechanical watch with automatic winding. Works when the engine is running. Meters of this type are rarely used, since they have been replaced by modern, convenient devices. Electromechanical meters are considered more reliable, accurate, and simpler. They have not lost their relevance for many years. They contain an electromechanical unit. A quartz resonator keeps track of the clock. Unlike such devices, electronic meters have a recorder (indicator). This is usually an LCD display. They are compact in size and reliable. When using an electronic device, the user must protect the readings and store the data.

New modern meters are digital. They not only record operating time, but can monitor other indicators. The design is based on a microcontroller. The digital device can be programmed to meet specific needs. Such a device needs protection against data reset.

The functionality of MCH counters also varies. Their functionality may be basic. Then the device only counts the operating time of the motor, without taking into account other parameters. The device can record tachometer information and exhaust gas temperature. Some models are equipped with an alarm that goes off when the time runs out.

How does the hour meter work?

The device is operated according to the manufacturer's instructions. If the hour meter is professional, then it is installed and configured by qualified specialists. Household devices are used according to a simple principle. They are available for use. The owner must periodically check the device. If a malfunction occurs, the meter is replaced or repaired. The device must be protected from liquids, falls, and shocks. If used correctly, it will work for many years.

The counter operates simply. The clock mechanism is activated when the engine is started. All readings are reflected on the indicator. If the engine has stopped, the operation of the device ends. For this reason, operating time is only recorded when the engine is running. The device calculates the hour in the manner provided by its design.