Combustion engine comprises engine block made of aluminum alloy, crankshaft made of iron alloy, lower bearing block with running surface, and crankshaft bore in which crankshaft rotates

摘要

Combustion engine comprises an engine block (12) made of an aluminum alloy; a crankshaft (30) made of an iron alloy; a lower bearing block (34) having a running surface; and a crankshaft bore in which the crankshaft rotates. The lower bearing block is made of an aluminum-silicon alloy having a longitudinal expansion coefficient which compares with that of the crankshaft. Preferred Features: The aluminum-silicon alloy contains at least 25, preferably 33-35 wt.% silicon and a balance of aluminum. The engine further comprises a crankshaft housing (22) mounted on the lower side of the engine block. The lower bearing block is cast as one piece with the housing.