BMW 3 series E30

Since 1983-1994 of release

Repair and car operation

3.2.13. Repair of valves

THE GENERAL DATA

Places of deterioration of the valve

1. An end face 2. Проточка under crackers 3. A core (a part with the least deterioration) 4. A core (a part with the greatest deterioration) 5. A facet 6. A corbel

PERFORMANCE ORDER

1. Check up a valve condition (subsection 3.2.12 see). Strongly worn out valves replace. 2. If as a result of this check it will be found out that a valve condition satisfactory measure diameter of the valve in several places. Appreciable distinction of diameters specifies in deterioration of a core of the valve. At detection of appreciable distinction of diameters at least in two places the valve replace. 3. If a condition of valves satisfactory they should be ground in to saddles. If on saddles there are only insignificant damages, or the saddle was exposed to repolishing grinding in can be executed on мелкодисперсном structure. Крупнодисперсный притирочный it is necessary to apply structure only in case of detection of traces of deep development or a strong burn-out of saddles. In this case it is necessary to hand over a head of cylinders and valves on check to the skilled expert, whether it is necessary to define перезенковать saddles, or to replace loose leaves of saddles. 4. Before grinding in a head of cylinders put on an equal surface, combustion chambers upwards. 5. Put on a saddle facet a thin layer притирочной pastes. Grinding in carry out, turning the adaptation on 180 ° in both parties and periodically raising the valve for uniform redistribution of an abrasive material. 6. If the rough structure grinding in comes to an end after formation of a monotonous matte corbel on valve and saddle facets is applied. Wipe the valve and a saddle from the rests of paste and continue grinding in on мелкодисперсном structure. Grinding in is considered finished at formation on facets of the valve and a saddle of a uniform continuous corbel of grayish colour. The further grinding in is not supposed, as because of excessive development of a saddle its subsequent repair can become impossible. 7. After the termination of grinding in of all valves carefully wash out all details solvent.