Note: Bushings with retaining rings are supplied as spare parts. The bushings have an outer diameter increased by 0.2 mm and a reduced diameter of the valve hole.
1. Press out the defective bushing from the combustion chamber side using a special mandrel.
2. Insert the new bushing into the special mandrel.
3. Press the bushing from the camshaft side using a mandrel until the retaining ring rests against the cylinder head.
4. Ream the bore in the bushing using a reamer to 8.022-8.040 mm for intake valves and to 8.029-8.047 mm for exhaust valves. Then grind the valve seats, centering the tool on the bore in the bushing.