1. While the hydraulic jack of gaps of valves is established in a head of the block of cylinders, press it with the maximum force in a place where the yoke contacts with the gap jack. If the jack of gaps is serviceable, it will move down with great difficulty.
2. If by pressing the jack of gaps easily moves down, it is faulty and is subject to replacement.
3. If the jack of gaps elastic, probably got to it the air mixed with oil, thus execute the following actions:
Check level of engine oil.
Check, whether is air hit in engine oil the reason of the damaged oil filter or laying of the oil filter. After elimination of the reason of hit of air in engine oil, warm up the engine, and some time move on the car on small speed. Stop the engine and leave it for some minutes, then restart the engine and move on the car on small speed. To remove air from engine oil repeat this procedure several times within one hour.