2.11.5. Check of technical condition and repair

Head of cylinders. Carefully wash up a head of cylinders and clear oil channels. Remove a deposit from combustion chambers and from the surface of final channels with a metal brush.
Examine a head of cylinders. On support under necks of the camshaft and in openings under pushers of valves there should not be zadir and damages. Cracks in any places of a head of cylinders are not allowed. At suspicion on hit of cooling liquid in oil, check tightness of a head of cylinders.
For check of tightness close openings of the cooling shirt caps and force the pump in a shirt of cooling of a head of cylinders water under pressure of 0,5 MPas (5 kgfs/cm2). Within 2 min. leak of water from a head should not be observed.
It is possible to check tightness of a head of cylinders compressed air for what muffle openings of a shirt of cooling with adaptation 67.7871.9510 caps, lower a head of cylinders in a bathtub with the water which is warmed up to 60–80 °C and let's it get warm within 5 min. Then give in a head compressed air under pressure of 0,15–0,2 MPas (1,5–2 kgfs/cm2). Within 1–1,5 min. an exit of vials of air from a head should not be observed.
Fig. 2.56. Saddles of valves: I \new saddle; II \a saddle after repair; and — a saddle of the inlet valve; b — a saddle of the final valve

Saddles of valves. The form of facets of saddles of valves is shown in fig. 2.56. On working facets of saddles (a zone of contact with valves) there should not be dot sinks, corrosion and damages. Small damages can be eliminated with grinding of saddles. At the same time remove as little as possible metal. It is possible to grind as manually, and by means of the grinding machine.
Grind in the following order:
– insert the aligning core into the directing valve plug And. 94059 and profrezeruyta facet 15 ° mill And. 94092 for a saddle of the inlet valve or And. 94003 – for final. Mills are put on a spindle of A.94058;
– to a profrezeruyta facet 20 ° mill And. 94031 for a saddle of the inlet valve or And. 94101 – for final;
– to a proshlifuyta a facet 45 °, providing width of a facet and basic diameters of 34 and 30,5 mm. Facets are ground by conic circles And. 94100 for saddles of inlet valves and And. 94078 – for final. Buoys are put on on a spindle And. 94069.
At the time of contact of a circle with a saddle the grinding machine has to be switched off, otherwise there will be a vibration and the facet will be wrong.
After grinding carefully wash out saddles and channels of a head of cylinders and blow compressed air.
The directing plugs of valves. Check a gap between the directing plugs and cores of valves, having measured diameter of a core of the valve and an opening of the directing plug.
Settlement gap for new plugs: 0,022–0,055 mm for inlet valves and 0,029–0,062 mm — for final; the most admissible limit gap (at wear) 0,3 mm on condition of lack of the increased noise of the gas-distributing mechanism.

Fig. 2.57. Vypressovka of the directing plugs a mandrel And. 60153/R

If the increased gap between the directing plug and the valve cannot be eliminated with replacement of the valve, replace plugs of valves, using a mandrel for a vypressovka and a press fitting And. 60153/R (fig. 2.57).
Press the directing plugs with the put-on lock ring against the stop it in a body of a head of cylinders.
After a press fitting develop openings in the directing plugs of valves development And. 90310/1 (for plugs of inlet valves) and And. 90310/2 (for plugs of final valves). Then a proshlifuyta a saddle of the valve and, if necessary, bring width of a working facet to the necessary sizes as it is stated above.
Always replace Maslootrazhatelny caps of the directing plugs at repair of the engine new.
Replace the damaged maslootrazhatelny caps on the removed head of cylinders. For a napressovka of caps use a mandrel 41.7853.4016.
Valves. Remove a deposit from valves. Check whether the core is deformed and whether there are no cracks on a plate. Replace the damaged valve.

Fig. 2.58. The extreme sizes when grinding facets of valves: I \inlet valve; II \final valve

Check a condition of a working facet of the valve. At small damages it can be proshlifovat, maintaining a corner of a facet 45 °30 '±5’. At the same time distance from the lower plane of a plate of the valve to basic diameters (34 and 30,5 mm) have to be within 1,3–1,5 and 1,8–2,0 mm (fig. 2.58).

Fig. 2.59. A specification for check of an external spring of the valve

Fig. 2.60. A specification for check of an internal spring of the valve

Springs. Be convinced whether is not present on springs of cracks and whether elasticity of springs decreased for what check their deformation under loading (fig. 2.59, 2.60).
Pushers of valves. Check a condition of a working surface of a pusher. On it there should not be zadir and scratches. At damages replace a pusher.

Fig. 2.61. Bolt of fastening of a head of cylinders

Bolts of fastening of a head of cylinders. At repeated use of bolts they are extended. Therefore check whether length of a bolt of L (fig. 2.61) exceeds 135,5 mm and if it more, then replace a bolt new.
Adjusting washers. Working surfaces of washers have to be smooth, without забоин, scratches and zadir. On them there should not be a step or unilateral wear, a natir of metal. Concentric traces from extra earnings with camshaft cams are allowed.