I used to hear a lot about oil additives and decided to understand whether they are useful, if yes, how should they be applied.
I have found a lot of information concerning this question and now I will try to visualize and present it here in structured form. I have spent a lot of time on learning of this question, and hope that it will be useful and interesting for somebody. So I made such a scheme of engine service life.
Scale of engine wear speed
On horizontal scale-time (t), on vertical-speed of wear (V). You must have the question, why the curve of engine wear speed is decreasing at first, than it is rising? I will try to explain.
You can see on the metal surface of the engine which has rolled of the production line on macro level. The treatment of the surface is not ideal, and there are a lot of micro damages (in reality their sizes are less than several microns, picture on the scheme is greatly zoomed). All new engines need time for lapping of all metal surface inequalities, by this reason for the first time the engine has strongly wear. When the lapping in period is finished, the engine wear is reducing and engine units lap in to each other.
The main thing is that the oil film evenly covers all piston walls surfaces without its rupture. It is very important, because metal surfaces of new engines has many prominences, and oil film on this prominences became weak and finally it becomes ruptured and metal surfaces stays unprotected. It facilitates engine wear.
Oil film rupture
Then the engine metal surface becomes even. This period of engine life is named “the maturity period”, when units has lapped in to each other and oil film protects well the engine. The engine wear still lasts, but slowly. This period is named static wear. Than the last engine life period comes, it is named “Old age”. The engine metal surface becomes worn, quantity and size of damages is rising, oil burning starts and soon the engine can break out! Here the story of the engine comes to the end.
Now we will speak about oil additives. What is their purpose? Let’s think logically. On the first period, when engine units lap in to each other we could accelerate this period in order to reduce engine units wear. So, friction modifiers can do it, they also has another name- ceramics or sand. Most often, this type of oil additives contains serpentinite, which play the role of light abrasive material. It helps engine units lap in to each mother faster. In other words has the same effect as light scrubbing. But, the most important thing is that the use of friction modifiers is inappropriate after ending of lap in period, because it will be harmful for the engine. Also, serpentineplays the role of abrasive material and it can increase micro damages.
Serpentinite mineral. The most part of friction modifiers contain it.
You cannot see any micro clerances between engine units, While this mineral creates the film on piston walls. As soon as the mineral exfoliates gradually from the piston wall, clearances are increasing shortly and finally the engine can seize.
So, what should be used in this engine life period? There is another type of oil additive especially for this type of the engine life, named remetalizers. The main their advantage is that they contain particles of the alloy of soft metals, which under the high pressure and temperature fullfil micridamages of piston walls restoring their structure. And all of this can be made without use of any abrasives.
Remetalizer works in such way
By this way, engine life curve is prolonging till the start of the aging period and end of engine life, in the case of engine aging remetalizer extends engine life. It is very useful to use it when the engine is new or if the engine has already run.
The question arose why car manufacturers do not recommend to use remetalizer for extending of engine life period? I think that the reason is that it is not paying for them. Now the car service life lasts 5 (some of them 3 years), and car manufacturers do not need engines which can run 500 thousands of km. On the other hand, there are many other parts which can be damaged earlier. So here are my thoughts. What do you think about this issue?