General information about DOHC engine repair (Opel Vectra B)

The engine is a four-cylinder, twin overhead camshaft engine mounted transversely at the front of the vehicle and the gearbox on the left side. All major engine components are made of aluminum alloy, except for the plastic timing belt covers. The crankshaft has five bearings and is secured against axial movement by thrust half rings mounted on the central main bearing. The camshafts are driven by a timing belt. Each camshaft controls the valves via hydraulic tappets. Thus, no valve clearance adjustment is required. Lubrication is provided by an oil pump mounted on the right end of the crankshaft and drawing oil through a mesh filter located in the oil pan. The pump supplies oil through an externally mounted full-flow oil filter.

Repairs that do not require engine removal

The following operations can be performed on the engine installed in the vehicle:

• removing and installing the cylinder head;
• removal and installation of toothed belt and pulleys;
• replacement of camshaft oil seal rings;
• removal and installation of camshafts and tappets;
• removing and installing the oil pan;
• removal and installation of connecting rods and pistons;
• removing and installing the oil pump;
• replacement of crankshaft oil seal rings;
• engine/gearbox mount replacement;
• removing and installing the flywheel.

[Text copied from this portal OPELBOOK]