4.2.2. Check of compression pressure in engine cylinders

Kompressometra of two types are issued: with nozzles of clamping and carving type. The last are rolled in candle openings and provide more reliable measurement though their connection and is connected with a little big time expenditure.


1. Decrease in efficiency of return of the engine, an excessive consumption of oil and/or fuel should be considered as signs of excessive wear of internal components of the power unit. Measurement of compression pressure in each of cylinders of the engine will allow to contain a problem.
2. Check level motive oil and completeness of a charge of the rechargeable battery.
3. Warm up the engine up to the normal working temperature, then muffle it.
4. Disconnect system of ignition.
5. Mark and disconnect wire VV from spark plugs.
6. Carefully blow candle niches (it is possible to use the ordinary bicycle pump), then turn out spark plugs.
7. Transfer a butterfly valve to completely open situation, - block the gate drive, or ask the assistant to hold the accelerator pedal of completely squeezed out.
8. Densely screw a transitional nozzle of a kompressometr in a candle opening of the first cylinder of the engine.

Try not to strip a thread in a head!

9. Working according to instructions of manufacturers of the device, connect the remote switch to a starter chain.
10. Make sure that the ignition key is turned in position of OFF and by means of the remote switch turn the engine not less than on five turns of a bent shaft (the provorachivaniye has to last not less than 5 seconds). Consider and write down the indication of a kompressometr.
11. Working in a similar manner, serially measure compression pressure in the remained engine cylinders.
12. Compare among themselves results of measurements, - they should not differ more than for 25%. So, if the maximum indication makes 1034 kPa, minimum has to make not less than 75% of this figure, i.e. to be not lower than 779 kPa.
13. With excessively low pressure in any of cylinders it is necessary to fill in in it through a candle opening approximately a teaspoon of motive oil and to repeat check. If addition of oil leads to correction of a situation, therefore, excessive wear of piston rings and/or mirrors of cylinders takes place. Otherwise it is possible with rather high degree of probability to speak about a burn-out / mechanical damage of working facets of valves or their saddles (also the probability of violation of integrity of laying of a head of cylinders is not excluded). The reason of identical pressure decrease in two next cylinders usually is breakdown of a crossing point of sealing laying between these cylinders (addition of oil will not lead to correction of a situation). Hit in combustion chambers of oil and cooling liquid (usually is followed by emergence of dense white or blue smoke on an exhaust, - it is not necessary to confuse to the white smoke which is formed during warming up of the engine or at operation of the car in cold weather) can be regarded as one more confirmation of the fact of violation of integrity of laying, - check motive oil for existence of signs of presence at it of cooling liquid.