| 1. After dismantling of a head of the block to wash out all details in gasoline, to wipe and dry. To clear chambers of combustion and valves of a deposit.
| 2. To examine a block head. If there are cracks on walls of the chamber of combustion, traces прогара, etc., to replace a block head.
| 3. To check up by means of a metal ruler and probeов, whether planeness of a surface of the head adjoining to the block is broken. For this purpose a ruler to put an edge on a surface of a head of the block in the middle, lengthways and then across and probeом to measure a backlash between a surface of a head and a ruler. If the backlash exceeds 0,1 mm, a head replace or прошлифовывают. The minimum admissible height of a head of 132,75 mm. If at polishing the head height has turned out less, it is necessary to replace a head.
|4. To check up a head on absence of cracks, for this purpose to bring to one of apertures of a shirt of cooling a hose for a supply of compressed air. To muffle all apertures in a head wooden stoppers. To lower a head in a bath with water and a tax the compressed air under the pressure of 1,5 атм. In places where there are cracks, there will be air bubbles.
|5. To examine valves. At detection on a working facet of the valve of cracks, коробления the valve it is necessary to replace heads of the valve, a burn-out, deformation of a core.
|6. Insignificant risks and scratches on a working facet of the valve can be deduced grinding in. The valve to a saddle should be ground in as follows:
– To insert the valve into a block head;
– To put on a core of the valve the adaptation for grinding in of valves;
– To put on a working facet of the valve thin a layer притирочной pastes;
– To turn the valve by means of the adaptation in both parties, periodically pressing to a saddle. An external sign of satisfactory grinding in is monophonic matte-grey colour of a working facet and the valve.
|7. After grinding in carefully to wash out a saddle and the valve and carefully to wipe a pure rag for removal of the rests притирочной pastes.
|8. To check up tightness of the valve, to establish it in a block head together with springs and crackers. After that to put a block head on one side and to fill in in the channel closed by the valve, kerosene. If during 3 mines kerosene does not filter into the combustion chamber, the valve is considered tight. The sizes of the valve are shown on fig. the Sizes of valves of the four-cylinder engine.
|9. To check up a condition of springs of valves. The bent springs, and also with cracks or broken replace.
|10. To check up a condition of saddles of valves. On working facets of saddles there should not be wear tracks, bowls, corrosion, etc. Insignificant damages (etc.) can be deduced small risks, scratches grinding in of valves. More major defects eliminate polishing. At polishing it is necessary to sustain the sizes of a saddle specified in fig. the Sizes of a saddle of the valve.
|11. After polishing to grind in valves. Then carefully to clear and blow compressed air a block head that in the channels closed by valves, and in combustion chambers does not remain abrasive particles.
|12. It is necessary to consider that after polishing of a saddle the valve saddles more deeply. Therefore on engines with hydropushers of valves after polishing it is necessary to measure distance and between an end face of a core of the valve pressed to a saddle, and the top plane of a head of the block. If this size is less 33,8 mm for inlet valves and less than 34,1 mm for final, it is necessary to replace a block head as normal work of hydropushers of valves in this case is broken. Thus, reduction of a working facet of a saddle of the valve should not be more differences of the size and before grinding and the minimum admissible size and.
|13. To check up backlashes between directing plugs and valves. For this purpose to insert the valve into directing plug so that an end face of a core of the valve was заподлицо with an end face of the directing plug.
|14. To a valve head to establish an indicator leg. Moving the valve from an emphasis against the stop in a horizontal plane, to measure a backlash. If moving of the inlet valve exceeds 1,0 mm, and final – 1,3 mm, to replace plugs and valves. Diameters of cores of inlet and final valves various, therefore it is necessary to check plugs of inlet valves, inserting the inlet valve, and final – the final valve.