To add the oil seal to the camshaft, put it in the right cylinder head and then use a Camshaft Installer MD-998306 to tap it home. Apply a very thin coat of clean engine oil to the lip of the camshaft oil seal and to the Cam Seal Protector 6788 and press the protector onto the camshaft. Slide the camshaft towards the front, stick the seal protector down the seal tube and seat the camshaft and afterward, take out the seal protector. Apply the camshaft thrust plate with a gasket and then tighten three of its bolts to 28 Nm. Apply a fresh gasket to the EGR solenoid/valve and the rear of the cylinder head, fill the assembly into place and fasten the two mounting bolts to 30 Nm. Put the appropriate camshaft sprocket on the camshaft, using a 213 mm bolt for the right sprocket and a 255 mm bolt for the left sprocket, keeping the right sprocket from rotating with a 36 mm box end wrench while you tighten the bolt up to 102 Nm plus 90° turns. Line up the right camshaft gear with its timing mark and check that both the right camshaft and crankshaft timing marks are connected as well. Tighten the timing belt around the tensioner pulley as you move it from the crankshaft sprocket clockwise. Secure the tensioner in the housing, then tighten both bolts to 28 Nm so the camshaft marks are still in line. Withdraw the retaining pin to let the tensioner out, then turn the crankshaft sprocket twice and examine the timing marks; if they are not equal, repeat the procedure. During installation, the four identification marks on the rocker arm and shaft should point toward each other and all ten bolts should be tightened to 31 Nm. Carefully clean all surfaces on the cylinder head and cover, change the gasket or seals if they are bad, install the cylinder head cover and tighten the eight bolts to 12 Nm. Put in the spark plugs and twist them on until you reach 28 Nm, then install the ignition coils and their bolts to a justifiable strength of 6.7 Nm. Place the engine wire harness back in its original spot, plug the electrical connectors into the ignition coils and fasten the upper and lower timing belt front covers, loosening the timing cover bolts to the indicated torque values. When fitting the crankshaft damper, use Forcing Screw C-4685-C1 with Nut and Thrust Bearing from Crank Sprocket Installer 6792 and while doing so, tighten the damper bolt to 95 Nm after holding the damper in place with Damper Holding Fixture 9365. Hold the fan and install its bolts to secure it, plug the connector into the fan's power lead and pull the hose over the top of the assembly and push it into place. The next step is to set the accessory drive belt tensioner in place and hold it tight with a 34 Nm torque on the mounting bolt, before installing the accessory drive belt. Attach the upper intake manifold and air cleaner body, connect the negative battery cable and tighten the nut to 5 Nm, load the cooling system and let the engine run until it is at normal temperature, watching the cooling system for correct levels.