The crankcase is made of high mechanical strength cast iron.The crankshaft is supported by five main bearings.The cylinders are formed directly on the crankcase and are divided into three size categories plus one oversize.Special channels in the crankcase walls carry coolant and lubrication fluid.
LOWER CRANKCASE
Specifications
The lower crankcase is made from die-cast aluminium alloy with cast iron main bearing caps.The machining of the supports and main bearing caps is carried out together with the crankcase.The matching with the upper crankcase is achieved by means of bolts and locating dowels which guarantee the precision of the fitting.There is a bead of sealant between the two crankcases to prevent oil leaks.
Composition
The upper and lower crankcases are illustrated in the diagram below.
