Installing the cylinder head and valve mechanism D-245
If it is necessary to replace valve seats, use a set of special mandrels shown in the figures
It is recommended to install valve springs and valve seals using a special tool and mandrel shown in the figures
Cylinder head gaskets must be lubricated on both sides with a graphite paste consisting of 60% engine oil and 40% graphite (by weight).
Teflon rings must be placed on the metal edges of the holes for the sleeves.
Tightening the head mounting bolts (nuts) must be carried out in the sequence shown in Fig. 3. Tightening torque - 190-210 Nm.
The push rods should be installed in the holes of the cylinder heads so that the tips of the rods fit into the recesses of the push rods.
When installing the valve mechanism, the spheres of the adjusting screws must be aligned with the tips of the rods.
The stud nuts and valve mechanism mounting bolts must be fully tightened.
The gap between the rocker arm striker and the end of the valve stem on an unheated diesel engine should be: intake valves - 0.2 +0.05 mm; exhaust valves - 0.45-0.05 mm.
Adjustment must be done in the following sequence:
- - turn the crankshaft until the valves in the first cylinder overlap (the intake valve of the first cylinder begins to open, and the exhaust valve finishes closing) and adjust the clearances in the fourth, sixth, seventh and eighth valves (counting from the fan);
- - then turn the crankshaft one revolution, setting the overlap in the fourth cylinder, and adjust the clearances in the first, second, third and fifth valves.
To adjust the gap, loosen the lock nut of the screw on the rocker arm of the adjustable valve and, turning the screw, set the required gap using the feeler gauge between the rocker arm striker and the end of the valve stem.
After setting the gap, tighten the locknut. After adjusting the valve clearance, install the cylinder head cover cap.
Checking the tightness of the cylinder head bolts should be done after running in and every 40 thousand. kilometers on a warm diesel engine.
Check the gaps between the valves and rocker arms and, if necessary, adjust them every 20 thousand km, as well as after removing the cylinder head, tightening the cylinder head bolts, and when valve knocking occurs.
Valve clearances must be checked at a temperature of no more than 60°C.