Engine hours: how to recognize and use them

It is not clear why automakers still rarely install hour meters on their products. The exception is some brands of heavy trucks that run on diesel fuel, and partly expensive cars of famous brands. Similar devices have long been available on almost all agricultural machinery.


Also, hour meters are installed on many snowmobiles and other similar machines - most often the parameter is already in the on-board computer. What is this characteristic and why is it not indicated in most car manuals.

About oil resource

Any tractor driver will tell you that you need to change engine lubricant using a special meter. Previously, it was mechanical and located somewhere near the engine units. Today, we install electronic devices or integrate an hour meter, for example, into a speedometer. Readings can be read directly in the cockpit.


The service books of most cars indicate that the engine oil must be changed every 10-15 thousand kilometers. But, however, there are also reservations. In case of “severe operating conditions”, the mileage should be reduced by approximately half. Where does this data come from? Naturally, the manufacturer tested its products, but, as a rule, at stands. And there the engine is in ideal conditions: the air and coolant temperatures are monitored, and only high-quality fuel is poured. Hence these results. But in practice everything may be different.

Oil change by engine hour

Obviously, the resource of mineral oil will be less than that of synthetics. On average, such an inexpensive composition is enough for a maximum of 200 m/h. For semi-synthetics, before replacement, the engine should ram a little more - 250 m/h. The service life of the next category of oil depends greatly on the manufacturer. There are both inexpensive synthetic compounds and “premium” ones. Therefore, here the replacement period ranges between 250 and 350 m/h. Sometimes on sale there is the so-called. “esters” (popularly sometimes called “supersynthetics”), which last even longer. But the price of such a composition is 3-4 times higher, compared even with the last type described. It is simply not economically feasible to pour such oil into the engine.

How to calculate engine hours

It seems that it’s easier if there is a counter: the crankshaft spins - the device begins to remember. But there is a nuance. It’s one thing when the engine rumbles at idle, and another thing when it accelerates, for example, with sudden acceleration. It is approximately believed that 1 hour of operation without load will be equal to 1 m/h.


When driving in normal mode with acceleration and braking for 60 minutes, we can already talk about 1,5 m/h. And if the car carries a load, a trailer, often goes uphill, etc., then we can say that 1 hour of such operation is equivalent to 3 m/h.

Operation in the city and beyond

For example, let’s take the average city-dwelling car owner. Let's say he goes to work every day, covering 15 km in half an hour. Morning warm-up and evening warm-up before returning take a total of 10 minutes. The same amount can be added to traffic lights and traffic jams (here, of course, there are options). Accelerations and overtaking, and these are increased loads, take 5 minutes, normal movement - 20 minutes. Let’s not bore the reader further with numbers, but move on to the conclusions: a couple of trips of half an hour, taking into account the above coefficients, “result” in 1,83 m/h. The average speed was 16,4 km/h.


It’s a different matter if most of the trip takes place outside the city limits, along the highway. Here, overtaking and acceleration are infrequent and take up approximately 10% of the total time. As a result, in an hour the engine becomes “older” by 1,65 m/h. And the average speed of the car reaches 54,6 km/h.

Elementary arithmetic

If we assume that the average engine oil life is 250 m/h (see above), then it turns out that with regular city trips at an average speed of 16,5 km/h, it is necessary to change the lubricant after 4 thousand 125 km (250 m/h). h (time) multiplied by 16,5). When driving on suburban highways, the oil change interval is 13 thousand 650 km. What if you drive a little around the city and the same amount on the highway? Then we take the average figure, which will be 8 thousand 875 km. That’s how it is: after so many kilometers of travel, manufacturers recommend refilling with fresh composition. But: “under severe operating conditions.”


When using pure synthetics, increase the interval by 20%. Reduce it by the same amount when the numbers on the odometer exceed 100 thousand km. The conclusions from here are simple: when determining the oil change period, you should not focus solely on mileage in kilometers. It is necessary to count engine hours, taking into account the operating mode of the engine. But how to do this if there is no standard device? You can buy and install it yourself: any car owner can do this procedure.

Types of hour meters

We will not consider the simplest, mechanical ones, because their time has passed and they can only be found today on retro equipment. Such devices are subject to mechanical wear, and it was impossible to reset the readings on them. They were installed at the factory and could not be found on sale.


However, sometimes you come across electromechanical versions: they are activated when voltage is applied (the drum rotates inside), i.e., when the ignition is turned on. Today, electronic devices are used, which for the most part are inexpensive and easy to install.

Meters powered by the ignition system

A common version of the meter that comes into operation as soon as it begins to “feel” high voltage pulses. For such a device to function, the induction method is used. In practice, this means that several turns of the signal wire (included in the kit) are wound around the high-voltage wire. Such devices correctly show the time the engine has worked, since they are activated when the crankshaft begins to rotate.


In addition, the meter is often also equipped with the function of an internal combustion engine speed meter - a tachometer. There are also disadvantages, but there are not many of them and, in fact, they are insignificant. If the device is installed in the cabin (this is not necessary), you will have to run the wire there. First, read the instructions for the product or the inscription on the packaging: the counter is separately configured (or initially intended) for two and four-stroke engines. Although there are also universal versions. The number of cylinders can also be taken into account.

Vibration counters

The simplest devices that are triggered by shaking from a running engine. There are no wires at all: the device is powered by a battery, which, according to user reviews, lasts for five years.


Such devices must be mounted directly on the internal combustion engine. But even this sometimes does not save from false positives. For example, the device may operate intermittently due to low vibration of the motor. And the price is somehow not very pleasing...

Meters operating when voltage is present

The devices are also quite simple: there are no signal wires, no need to change the battery. They are connected to where voltage appears after turning the ignition key. You can place such a device anywhere: even in the trunk.


The disadvantage is that the device is turned on when the engine is not running: that is, it will show a slightly higher number of engine hours than it actually is. However, the difference here is insignificant and can be neglected when changing the oil. Another thing is important: in any case, when using a meter, you will be able to more accurately determine the timing of engine lubricant replacement.