The simplest and most accessible way for every driver to diagnose an engine is to check the compression in the cylinders.
Performing a compression test
There can be any number of reasons for this: starting from the quality of the fuel and the operation of the fuel system, and ending (in the worst case) with a malfunction of the pistons, valves and the cylinders themselves. Do not forget to add here the defects in the seals.
Immediately, an unpleasant question is approaching like a formidable cloud - what, is it really necessary to do a major overhaul of the engine? The answer is unequivocal - no.
There are compression gauge readings, you need to put them into practice
If low compression is visible in one cylinder and the engine idling is unstable, then it is more likely that controls the exhaust valve.
If the compression is different according to the scheme: low in two adjacent cylinders, then, most likely, the gasket between them burned out.
And finally, after you added a little engine oil to each cylinder and repeated the compression test, the readings went up - the piston rings were worn out.
Methods for eliminating low engine compression
As we have already said, there are a lot of reasons that there is a different compression in the cylinders. And, if you follow the "smart" books, then you need an autopsy, which, as you know, will show the reason.
But just one thought that a heap of problems will fall on you is terrifying. And the replacement of rings, the replacement of "caps", crankshaft oil seals. And if it is broken, then the boring of the block cannot be avoided. No, don't worry about it just yet.
Therefore, the first possible reason for the formation of low compression in the cylinder, experts recommend considering the occurrence of the rings. This is when they get too coked and practically stick to the piston. If the option described below does not eliminate the problem of different compression in the cylinders, then radical methods will be needed.
Folk way to eliminate the occurrence of rings and increase compression
This method is not a guarantee that the compression meter readings will change. But, it is actually effective if different compression in the cylinders was formed precisely because of the occurrence of the rings. At a minimum, your conscience will be clear, and then you will exclude this item from the diagnosis.
- We purchase high-quality liquid for cleaning valves. The instructions for it should indicate that it is added to engine oil.
- Tonight, we unscrew all the candles and pour 50-70 ml into cylinders. this liquid with a "pear" or syringe.
- In the morning, after 12 hours, scroll the engine, then clean the candles and adjust the gaps, and only then screw them into place.
- When starting the engine, do not be alarmed by the quality and quantity of smoke from the exhaust system.
- Drive onto the road to pass sections at higher speeds. That is, the task is to give the engine maximum load. Therefore, think in advance where you will do it. Consider the condition of the road surface, weather conditions, traffic intensity. Ideally, this is done on a country road.
- Important! The previous point must be fulfilled without fail, otherwise the coking products that have come off overnight will fall under the valve and then the cylinder head disassembly cannot be avoided.
- After running at a speed of 100-120 km / h in a section of 10-20 km. re-measure the compression in the cylinders.
There are two options here: joy and a feeling of happiness from the seen numbers of the same compression, which corresponds to the norm. Or bitterness from the upcoming operation with and engine diagnostics. There is no third.
Good luck with eliminating the difference in compression in the cylinders.
