Dismantling of a head of the block of cylinders is carried out in the following sequence:

– remove a head of the block of cylinders

(see подразд. 3.1.6);

– unscrew bolts of fastening of an inlet collector and a nut of fastening final, remove collectors;

– remove a camshaft (camshafts) and hydraulic pushers (see подразд. 3.1.5);

Fig. 3.15. Compression of springs of the valve by the special adaptation and removal of crackers of the valve

– compress valve springs the special adaptation and remove valve crackers (fig. 3.15) ;

Fig. 3.11. Head of the block of cylinders of the SOHC engine and mechanism of a drive of valves: 1–camshaft; 2–cover of the No. bearing of 1 camshaft; 3–cover of the No. bearing 2 camshafts; 4–cover of the No. bearing 3 camshafts; 5–cover of the bearing No. 5 of a camshaft; 6–gear pulley of a camshaft; 7–bolt of fastening of a pulley of a camshaft; 8–head of the block of cylinders; 9–hydraulic pusher; 10-valve crackers; 11-plate of a spring of the valve; 12-external spring of the valve; 13-internal spring of the valve; 14-maslosjemny cap; 15-bottom plate of a spring of the valve; 16-the directing plug of the valve; 17-valve; 18-cuff; 19-cap; 20-nut of fastening of a cover of the bearing; 21-segment shponka; And — a place of drawing of alphabetic marking of a camshaft; B – a place of drawing of digital marking of a camshaft

– release springs and remove the top plate 11 (see fig. 3.11 ) springs of the valve and a spring 12 and 13;

– take the valve from a head of the block of cylinders from the combustion chamber;

– remove other valves in the same way;

– remove maslosjemny caps 14;

– remove the bottom plates of 15 springs of valves;

– put sets of details for each valve in the separate marked packages for the subsequent their installation on the places.

Cleaning and sink of details. Before check of a condition of details execute the following operations:

– remove the remains of old laying and hermetic from a head of the block of cylinders with a wooden or plastic scraper;

– clear cavities in a head of the block of cylinders a wire brush;

– clear combustion chambers of a deposit, wash out a head of the block of cylinders solvent;

– wash out and blow the compressed air oil channels and channels of system of cooling of a head of the block of cylinders.

Defektovka heads of the block of cylinders includes the following operations:

– check of a head of the block of cylinders on existence of chips, cracks and other damages. In the presence of cracks a head replace;

– check of a privalochny surface on existence of jags, deep scratches and other damages. If it is impossible to eliminate these defects with plane grinding, a head of the block of cylinders replace;

Fig. 3.16. Check of planeness of a privalochny surface of a head of the block of cylinders

– check of planeness of a privalochny surface of a head of the block of cylinders by means of a testing ruler and щупа (fig. 3.16) . If the gap between an edge of a ruler and a surface exceeds 0,1 mm, it is necessary to replace a head;

Fig. 3.17. Profile of a saddle of the inlet valve: a= 37,20 mm (engines of 1,6 l); a= 39,20 mm (engines of 1,8 l); b= 2,0 mm

Fig. 3.18. Profile of a saddle of the final valve: a= 32,40 mm; b= 2,4 mm

Fig. 3.19. Distance from an end face of a rod of the valve to the top surface of a head of the block of cylinders

– visual survey of saddles of valves. If on saddles of valves wear tracks or burnings are found, saddles should be ground. Profiles of saddles of valves are shown on fig. 3.17 and 3.18 . After polishing of a saddle it is necessary to insert the valve, to press it against the stop to a saddle and to check A distance (fig. 3.19) from an end face of a rod of the valve to the top surface of a head of the block of cylinders. Minimum admissible value of this distance for inlet valves of 33,8 mm, for final valves – 34,1 mm. If it is less, it is necessary to replace a head of the block of cylinders. After any processing of saddles of valves it is necessary to execute their grinding in with valves;

– measurement of values of internal diameter of directing plugs of valves. If values exceed the most admissible size, replace directing valves with HUNDRED.

PREVENTION After replacement of the directing plug of the valve grinding of its saddle is necessary.

Defektovka of details of the klapanny mechanism.

Examine plates of valves. At existence on them dot corrosion, прожогов, cracks and wear replace valves.

If a valve condition satisfactory, measure diameter of a core of the valve by a micrometer in several places. At considerable divergences of values of measurements, i.e. at wear of a core, replace the valve.

Before installation of valves it is necessary to grind in them with use of pritirochny paste — mixes of a small abrasive powder with engine oil. Put paste on a saddle surface, insert the valve, establish on it присос adaptations for притики and rotate the adaptation in both parties, periodically pressing the valve to a saddle. After the completion of grinding in clear all details of dirt and the paste remains. Check correctness of a prileganiye of the valve to a saddle — on a saddle and a plate of the valve there should be continuous opaque corbels in width about 2 mm.

Fig. 3.20. Check of an axial deviation of springs

Examine springs of valves. In the presence of any damages they are subject to replacement. Measure values of length of springs in a free condition and compare to such values of new springs. Establish springs on a flat horizontal surface and check their deviations from axes (fig. 3.20) . If though one of springs of the valve is bent, replace its both springs.

Examine crackers and pro-points on cores of valves for installation of crackers. In the presence of any damages replace details.

If when dismantling a head of the block of cylinders maslosjemny caps acted in film, it is necessary to replace them.

Assembly of klapanny mechanisms is carried out in the following sequence:

– grease a core of the valve and directing plug with pure engine oil, insert the valve;

– establish the bottom plate of springs of the valve;

– erase engine oil from the top part of a core of the valve;

– establish the plastic plug or wrap up a sticky tape a pro-point of a core of the valve for installation of crackers for protection from damages of working edges of a maslosjemny cap at its installation;

Fig. 3.21. Installation of a maslosjemny cap in an assembly opravka: 1–assembly opravka; 2–maslosjemny cap

– grease with fresh engine oil a working edge of a maslosjemny cap 2 (fig. 3.21) and establish it in an assembly opravka 1;

– напрессуйте against the stop a maslosjemny cap for the end of the directing plug of the valve careful blows of a hammer on an opravka, having an opravka strictly on an axis of the directing plug;

– remove the plastic plug or a sticky tape from a valve core;

– establish springs of the valve and their top plate;

– compress valve springs the special adaptation (see fig. 3.15 ) and establish crackers, propping up the valve from the combustion chamber, then slowly remove the adaptation for compression of springs;

– collect the remained klapanny mechanisms in this way;

– strike on the valve end with a copper hammer so that it was slightly opened and all details of the klapanny mechanism rose on the places.