As a power plant in Mazda 3 cars, 4-cylinder engines are used, in which the cylinders are arranged in one row. From below, the engine is closed by a sump that forms a crankcase, which is also a reservoir for oil, which is necessary for lubrication, cooling and protection of engine parts from wear.
All three engines are 16-valve, with four valves per cylinder. The valves are actuated by two overhead camshafts via poppet followers.
This section describes inspection procedures and repair operations without removing the engine from the vehicle, then discusses in detail the removal and installation procedure, and also describes the repair of parts located in the block and cylinder head.