Contents: Removal ⤓ Installation ⤓
Removal
Remove the cylinder head, see p. 1.8.
Remove the intake and exhaust manifolds.
Note: When reinstalling valve control parts, they must be installed in their original locations. To avoid confusion, it is recommended to stack the parts in order on a special board.
Remove the camshaft, see item 1.9.
Caution: When removing the Jet valve (not available on all engines), make sure that the key is inserted straight. Otherwise, the valve may break off.
1 - lower valve spring plate,
2 - valve stem seal,
3 - valve spring,
4 - upper valve spring plate,
5 - valve crackers.
The material was created based on the website MitsubishiMan.ru
Remove all valves one by one. To do this, compress the valve spring with a special spring compression device and remove the crackers from the valve stem.
Pull out the valve seal with pliers. Old seals are often quite tight. In this case, it is recommended to use a punch, for example, HAZET 791-2
Pull out the valve from the combustion chamber side.
Installation
Before installing the valves, check the valve guides and, if necessary, process or grind the valves, see p. 1.1.
Caution: New valve spring retainers are often very sharp at the bottom edge of the cracker hole. This can cause damage to the valve stems (scratches, etc.). Replace damaged valves, if necessary, sand the valve spring retainers before installation.
Sand the valve stems on the surfaces where they contact the crackers.
Lightly lubricate the valve stem and valve guide with engine oil and insert the valve. Do not mix up the intake and exhaust valves!
Insert the lower spring pad.
Lightly lubricate the new valve seal with engine oil and press it in with a suitable punch until it stops. The picture shows a diesel engine with the MD-998 729 installation tool. For other engines, the following tools are used in the workshop: 12-valve engine MD-998760, 8-valve engine: MD-998302, 16-valve engine: MD-998729, Jet valve: MD-998308.
From a safety point of view, it is essential to replace the valve seals.
Caution: To prevent damage to the valve stem seals, cover the valve stem to cracker mating surface with smooth adhesive tape before installation. Remove the tape after installation. Otherwise, the valve stem seals may be damaged. The engine will then have increased oil consumption.
Insert the valve spring and the upper valve spring plate. Install only springs of the same wire diameter and length. The painted side of the valve spring must face the rocker arm.
Compress the valve spring with spring compression pliers and insert the crackers so that they pop into the valve groove. Be careful not to damage the stem seal with the pliers when compressing the spring. Loosen the pliers and insert the next valve.
If it was removed, screw in the Jet valve by hand (not available on all engines). First, insert a new sealing ring into the valve body and apply a little motor oil to the threads and seating surface (the surface where the valve fits onto the cylinder head). Tighten the injector valve to 9 Nm. Make sure that the key is inserted without tilting, otherwise the valve may break off.
Install the camshaft, see item 1.9.
Install the intake and exhaust manifolds with new gaskets and tighten alternately.
Replace cylinder head gasket, install cylinder head, see p. 1.8.