General information about engines (Chevrolet Trailblazer 1)

This chapter describes repair procedures that can be performed without removing the 4.2L inline six-cylinder engine. The engine block, cast from aluminum alloy, contains six cylinders arranged in a row. The aluminum cylinder head contains two camshafts, which drive four-valve mechanisms on each cylinder. The valves are driven by roller rocker arms, which are in direct contact with the camshaft lobes. The clearances between the camshaft lobes, rocker arms and valves are automatically maintained by hydraulic compensators. The oil pump, driven directly by the crankshaft, is located in the front engine casing. The cylinder block pan is cast from aluminum alloy. The crankshaft is made of hardened steel. The pistons are completely unloaded; the connecting rods are stamped from powder alloy.

To correctly identify the engine, you need to find the corresponding plate, which is located in the left front corner of the instrument panel. The VIN number is visible from the outside of the car through the windshield. The eighth character in the engine designation indicates its type:

S = 4.2 litre in-line six-cylinder engine.