Removal
1. Remove the cylinder head cover.
2. Remove the ignition distributor.
3. Remove the timing belt, camshaft pulley and upper timing belt cover.
4. Using a dial indicator, measure the camshaft end play.
5. If the camshaft play exceeds the permissible limits, the camshaft and/or cylinder head must be replaced.
Examination
1. Measure the distance between the ends of the camshaft gear retaining spring ring.
2. Mark and remove the tappets along with the adjusting plates.
3. Inspect each lifter for wear and scratches.
4. Check the camshaft bearing running surfaces and camshaft lobes for wear. If any wear is present, replace the camshaft.
5. Using a micrometer, measure the height of the camshaft lobes...
6....and the diameters of the camshaft bearing journals.
7. Check the camshaft bearing clearance as follows.
7a. Clean the bearing caps and camshaft journals.
7b. Install the camshaft into the cylinder head, but do not install the tappets or lubricate the camshaft.
7v. Cut a piece of Plastigage plastic rod (it should be slightly shorter than the width of the bearing) and install it on the camshaft journal.
7g. Install the bearing cap with the arrow on the bearing cap facing the front of the engine.
7d. Tighten the camshaft bearing cap mounting bolts to the specified torque and in several stages.
Caution: Do not rotate the camshaft while measuring the working clearance using the Plastigage method.
7th. Unscrew the bolts and remove the camshaft bearing cover.
7zh. Apply a scale ruler to the deformed plastic rod. By comparing the width of the deformed plastic rod with the control width on the scale ruler, determine the size of the working gap.
7z. Finally, thoroughly clean any traces of Plastigage material from the bearings and camshaft.
8. Temporarily install the camshafts without tappets into the cylinder head and measure the clearance between the camshaft gear teeth.
Installation
Camshaft controlling the intake valves
1. Lubricate the tappets with clean engine oil and install them in place. Make sure the adjusting shims are installed in the tappets.
2. Lubricate the bearing journals and camshaft lobes with clean engine oil.
3. Install the camshaft into the cylinder head so that the alignment pin is turned 80° to the left of the vertical line.
4. Apply a thin layer of sealant to the mating surface of the front camshaft cover as shown in the figure.
5. Install the camshaft bearing caps according to the marks, with the arrows pointing towards the front of the engine.
6. Tighten the camshaft bearing cap bolts gradually and sequentially in the order shown in the illustration.
7. Install a new camshaft oil seal ring.
Camshaft controlling the exhaust valves
1. Lubricate the tappets with clean engine oil and install them into the cylinder head along with the adjusting shims.
2. Lubricate the camshaft cams and bearing journals with clean engine oil.
3. Turn the camshaft controlling the intake valves to a position where the alignment pin is positioned 10° to the left of the vertical line.
4. Install the camshaft controlling the exhaust valves into the cylinder head so that the marks on the shaft gears are aligned.
5. Install the camshaft bearing caps according to the identification marks, with the arrows on the caps facing the front of the engine.
6. Gradually and sequentially, in the order shown in the figure, tighten the camshaft bearing cap bolts.
7. Install the timing belt pulley onto the intake camshaft and tighten it to the specified torque, while holding the camshaft from turning with a second wrench.
8. Install the timing belt.
9. Further installation is carried out in the reverse order of removal.