1 - valve; 2 - oil seal; 3 - lower spring plate; 4 - valve spring; 5 - upper spring plate; 6 - crackers
Attention! All parts removed from the engine cylinder head must be marked and arranged according to the cylinder numbering.
The valve must be removed in the following order. Remove the cylinder head and camshafts. Mark and remove the hydraulic tappets. Remove with special pliers - device "11.1.480" (fig. 3.125) oil scraper caps from valve guide bushings.
Press the valve spring using special pliers or a standard device (see fig. 3.129) and take out the crackers.
Remove the top plate (5, see Fig. 3.124) valve springs.
1 - valve; 2 - oil seal; 3 - lower spring plate; 4 - valve spring; 5 - upper spring plate; 6 - crackers
Remove the valve spring (4). Remove the valve (1) from the combustion chamber side of the cylinder head. Remove the lower valve plate (3). Remove all valves in sequence.
The valves should be installed in the reverse order, while checking the clearance (see fig. 3.7) valve stem/guide bushing and, if necessary, restore the tightness of the valve guide bushings by processing them with a reamer (see fig. 3.70).
Install (temporarily) the valve and check and, if necessary, restore the tightness of the valve fit to its seat by lapping (see fig. 3.6).
Remove the valve being installed and remove traces of the process of restoring the tightness of its seat.
Caution: If new valve spring retainers have sharp inner edges, they must be removed before installing the retainer on the engine cylinder head.
Remove sharp edges from the grooves of the valve stem under the crackers. Install the valve, having previously lubricated its stem and guide with engine oil. Install a new valve stem seal.
Install the lower valve plate and its spring. The upper and lower valve spring plates are different, because the spring has a conical shape. The spring rests on the cylinder head with its larger diameter.
Install the upper valve spring plate. Press (compress) the valve spring with special pliers and install the crackers so that they fully enter the grooves on the valve stem. Smoothly release the pliers, strictly monitoring the position of the crackers.
Install the remaining valves in the same way. Do not mix up the inlet and outlet valves and their installation locations.
Lubricate the hydraulic tappets with engine oil and install them in their original locations according to the markings.
Install the camshafts. Check the axial clearance of the camshafts; the principle of measuring it is shown in Fig. 3.87.
Replace the cylinder head gasket with a new one. Assemble the engine.