5.14.5. Grinding in of valves

Grinding in of valves is carried out on the removed head of the block of cylinders (see. "Replacement of laying of a head of the block of cylinders"). For extraction of valves from the directing plugs of a head of the block of cylinders it is necessary to remove springs of valves, having squeezed them special adaptation and having taken out crackers from plates of springs (see. "Replacement of oil scraper caps of valves"). For grinding in of valves it is the most convenient to use special mechanical adaptation (a reversive drill).
Besides, on sale there are ready tame holders of the valve.

Fig. 5.10. Device for grinding in of valves: 1 – metal core; 2 – rubber hose; 3 – screw collar

In the absence of ready devices it is possible to use adaptation manufactured according to the drawing of fig. 5.10.
Besides, it will be required to you: pritirochny paste, kerosene, the weak spring which on outer diameter is passing in a valve saddle opening.
1. Clear the valve of a deposit.
2. Apply a continuous thin film of pritirochny paste on a valve facet.
3. Put on previously picked up spring a valve core and insert the valve into the directing plug from the combustion chamber, having greased a valve core with a layer of graphitic lubricant.

Note
Graphitic lubricant protects the directing plug from hit in its openings of an abrasive from pritirochny paste and facilitates rotation of the valve during grinding in.

4. Put on a valve core the device for grinding in of valves (or with some tightness a rubber tube for connection of the valve with a reversive drill).
5. Having included a drill on the minimum frequency of rotation (in reverse mode) or rotating adaptation (in case of manual grinding in) alternately in both parties half way, grind in the valve, periodically pressing it to a saddle, weakening effort of pressing.
6. Grind in the valve before emergence on its facet of an opaque gray continuous monophonic corbel not less than 1,5 mm wide, at the same time …
7. … on a valve saddle after grinding in the brilliant corbel not less than 1,5 mm wide also has to appear.
8. After grinding in wipe a saddle and the valve with a pure rag and carefully wash out for removal of the remains of pritirochny paste.

Prevention
Do not grind in valves by means of the high-speed irreversive electric drill as in this case it will not be possible to achieve a qualitative surface (without circular risok) the ground-in facets and, besides, perhaps excessive attrition of contact surfaces of the valve and a saddle that will lead to deterioration in tightness and a bystry progar of valves.

9. Check tightness of the valve, for this purpose install it in a block head together with springs and crackers. After that put a block head on one side and fill in kerosene to the canal closed by the valve. If within 10 min. kerosene does not filter into the combustion chamber, the valve is considered tight. If kerosene filtered into the combustion chamber, then grind in the valve once again.
10. Similarly grind in other valves and check their tightness.