Generally, we think of one cylinder block in connection with all cylinders of an engine. Some engines, however, may have a separate block for each group of cylinders. Transverse members provide rigidity and strength, ensuring alignment of the bores and bearings under all loads. The block is bored to receive the cylinder liners. Note the air inlet ports in the cylinder bores and the water jackets which extend to the full length of the bores.
Air space surrounds the water jackets.
Through this space, commonly called the air box, air is conducted from the blower to the inlet ports of the cylinder liner. Other parts, which are cast integral with this type of block, are the upper halves of the main bearing seats, handholes, bore for the cam or balance shaft, lubricating oil passages, and coolant passages. Cutaway view of a cylinder block showing air and water passages. Water passages are cast in the block to provide coolant to the cylinder liners and the cylinder heads. Main oil galleries are drilled in the block to direct lubricating oil to the crankshaft main bearings and related parts.