2. Setting the piston of the 1st cylinder to the TDC position is an important condition for many procedures, such as replacing the drive chain and replacing the camshaft.
3. Locate the high-tension wire terminal of cylinder 1 on the distributor cap. If the terminal is not marked, trace the high-tension wire from the spark plug of cylinder 1 to the cap (cylinder No.1 is located on the engine side on the drive chain].
4. Remove the camshaft cover as described in paragraph 4.
5. Using a suitable wrench socket on the vibration damper hub bolt/crankshaft pulley, turn the crankshaft clockwise until the following marks are aligned: (see Fig. 3.5, a, b).
- a) The TDC mark "O"/"T") on the crankshaft pulley is aligned with the edge of the crankshaft position sensor support bracket.
- b) TDC rod or hole (depending on the engine type) on the flange at the front of the camshaft, it is aligned with the protrusion on the front bearing cover of the camshaft.
- c) The distributor rotor is aligned with the mark on the outer rim of the distributor housing (it may be necessary to remove the distributor cap to see the mark - see Chapter 5B).
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Fig. 3.5, a. TDC mark ("O"/"T") (shown by arrow)on the crankshaft pulley / vibration damper aligned with the edge of the crankshaft position sensor support bracket
Fig. 3.5, b. The TDC rod (1) on the camshaft is aligned with the protrusion (2) on the bearing cap
Fig. 3.5, c. TDC marks on the camshaft
A Late models of shaft with TDC hole(1)
In Early Models of Shaft with TDC Pin (2)
6. When the marks are aligned as described in point 5, the piston of the 1st cylinder will be in the TDC position. If the camshaft drive chain is removed, do not turn the crankshaft until the chain is reinstalled.