2.9.15.8. Cleaning of a deposit, grinding in of valves and restoration of a head of cylinders

 PERFORMANCE ORDER

  1. On the removed head of cylinders remove a deposit and deposits from the surfaces of combustion chambers and openings by means of a stupid scraper. Clear a head of cylinders of scale, the remains of old laying or sealing paste. Wash out a head kerosene and surely stretch a piece of rags through windows and openings for bolts of a head of cylinders since the dirt particles which remained in these deepenings can get on laying or the surface of the block of cylinders during its installation and to lead to a leak after assembly.
  2. If at a pure head of cylinders the leak of cooling liquid is found, check a head for deformation. For this purpose use a ruler and probes or mirror glass. If the curvature of a surface exceeds 0,08 mm, restore a head surface grinding. Track that the minimum distance between a plate of the valve and the surface of laying corresponded to technical characteristics.
  3. Clear pistons and the top part of openings of cylinders. If pistons still are in the block, be careful not to allow hit of particles of a deposit in cylinders since it can scratch their walls, damage pistons and rings. Turn a bent shaft and clear other pistons and openings of cylinders of a deposit.
  4. Carefully remove deposit particles from openings of cylinders, and then pour a little liquid oil around edges of pistons for lubricant of piston rings.
  5. Examine plates of valves (especially final), be convinced that on them there is no vykrashivaniye and an obgoraniye. At the same time examine saddles of valves. If saddles burned only slightly, defects can be eliminated with simultaneous grinding in of valves and their saddles at first rough, and then thin pritirochny paste. At strongly painted saddles of valves it is necessary to proshlifovat them before receiving a corner of a cone of a saddle in 45 ° again. Valves usually strongly wear out and burn therefore they need to be replaced and ground in to saddles.
  6. For grinding in of valves apply a little rough karborundovy structure on a saddle of the valve and establish "ground in" with prisosy on a valve head. Rotating "ground in" alternately on 180 °, grind in a plate of the valve to a saddle, from time to time raising the valve to redistribute pritirochny structure. When on the valve and a saddle there is an equal opaque strip, remove structure and repeat grinding in with thin karborundovy structure, turning and raising the valve as it is stated above. When on the valve and on a saddle the equal continuous light gray strip appears, operation of grinding in can be considered finished.
  7. Remove all deposit from a head and a core of the valve. Completely clear them of pritirochny structure, carefully watching that there is no its trace left in channels and in the directing plugs of valves. Clear valves and saddles at first the rags impregnated with kerosene, then dry rags and an obduyta the valves directing plugs and channels.
  8. For check of wear of the directing plug of the valve insert into it the new not worn-out valve and check whether it shakes here and there. If shakes, remove the directing plug from a head of cylinders by means of a mandrel. Outer diameter of a guide is slightly more (on +0,012 mm) to keep its landing with a tightness in a head of cylinders. Before installation of a guide heat a head of cylinders to 80 — 90 °, and cool a guide in liquid nitrogen or artificial ice if it is possible. Insert a guide so that the spring cutting ring smoothly adjoined to the top surface of a head of cylinders.
  9. Check length of valvate springs in a free state, comparing it to a new spring, and replace them if it is necessary.
  10. Check crackers of plates of springs where they are available, and if it is necessary, replace them.