Note: The inlet and exhaust camshafts are different. They can be identified by a raised feature in the centre of the exhaust camshaft, which is machined off on the inlet camshaft. The camshafts can be further identified by a letter I for inlet or E for exhaust stamped on the end of the sprocket boss.
1. Inlet camshaft; 2. Machined section; 3. Exhaust camshaft; 4. Raised section
Caution! Never fit a camshaft sprocket to a camshaft using incorrectly identified bolt holes. Severe engine damage will result from incorrect attachment.
The same sprocket is used for both inlet and exhaust camshafts, and is attached to the camshaft using slotted bolt holes. The same holes are used when fitting the sprocket to either camshaft.
Note that the mark on the camshaft boss is not a timing mark, it is used as a visual aid during the timing adjustment procedure.
Accurate camshaft timing can only be obtained using the correct timing method and service tools as described on Camshaft - Installation and Timing in this chapter.