Fig. 2.273. Plate thickness of the valve

Proshlifuyte valves before elimination of traces of a deposit and scratches. Make sure that the ground-in facet of the valve forms a corner 44,5 ° concerning the plane, a perpendicular axis of a core. Check thickness of a cylindrical part of a plate of the valve (fig. 2.273).

Standard thickness of a plate – 1,0 mm.

If thickness of a cylindrical part of a plate of the valve is less than minimum admissible value, replace the valve.

Fig. 2.274. Valve length

Check the total length of the valve (fig. 2.274). If total length is less than minimum admissible, replace the valve.

Nominal length:

the inlet valve – 95,45 mm;

the final valve – 95,40 mm.

Minimum total length:

the inlet valve – 94,95 mm;

the final valve – 94,90 mm.

Check a condition of a face surface of valves regarding wear existence. If the end face of the valve is worn-out, to a pereshlifuyta an end face or replace the valve.

NOTE After regrinding check the total length of the valve. Then a mill from solid alloy with a corner of a cone 45 ° to a proshlifuyta of a saddle of valves, having removed the minimum layer of metal only for cleaning of working facets of saddles. Check correctness of landing of the valve in a saddle. Apply a thin film of whitewash on a valve facet. Press a working facet of the valve to a saddle, but do not rotate the valve. Then remove the valve and examine a saddle and a facet of the valve.

If paint remains on all circle (360 °) valve facets, then the valve концентричен. Otherwise replace the valve. If paint is shown on all circle (360 °) valve saddles, directing (plug) of the valve and a saddle of the valve of a kontsentrichna. Otherwise to a pereshlifuyta facet. Make sure that the spot of contact is in a middle part of a working facet of the valve and has width of 1,0-1,4 mm.

Fig. 2.275. The scheme of regrinding of a saddle a mill with a corner of a cone 30 ° and 45 °

Otherwise correct a facet so that the spot of contact was not located too highly on a valve facet. For regrinding of a saddle use mills with a corner of a cone 30 ° and 45 ° (fig. 2.275).

Fig. 2.276. The scheme of regrinding of a saddle a mill with a corner of a cone 75 ° and 45 °

If the spot of contact is located too low on a valve facet, then for regrinding of a saddle use mills with a corner of a cone 75 ° and 45 ° (fig. 2.276).

Manually grind in the valve and a saddle of the valve with use of abrasive paste. After grinding in clear the valve and a saddle of the valve.