Top dead center (TDC) of piston No. 1 (Opel Omega B)

The top dead center is taken to be the highest point reached by piston N1 during the compression stroke.

Piston N1 is located at the front of the engine on the timing belt side.

1. Disconnect the negative battery cable and, if necessary, remove the spark plugs.

2. Remove the outer timing belt cover.



3. Turn the crankshaft so that the timing mark (1) of the camshaft sprocket aligns with the slot in the rear timing belt cover, and the mark (2) of the crankshaft sprocket aligns with the slot in the oil pump housing.

4. When the marks are aligned, piston N1 is at TDC during the compression stroke.

(Text copied from this portal: Opelbook.ru)