Cylinder block

An engine block is part of an internal combustion engine. He combines in addition to the cylinders and the crankshaft bearing and water-cooled engines the water jacket. In technical term, however, the bond is called for the said components crankcase. On the engine block usually is the ability to secure the necessary for the operation of the engine ancillaries.

Main tasks

The main tasks of the engine block are

• Transmission of dynamic forces ( inertia and gas forces ) of an engine,
• Crankshaft bearing,
• And often the camshaft ( except when this is in the cylinder head ),
• Together with the oil pan and conclude the machine room,
• Connection to provide for storage of the engine in the vehicle,
• Inclusion of auxiliaries and
• Of the cylinder head
• And recording of any existing cylinder liners.

Due to the variety of tasks the crankcase is also subject to many stresses, such as moments of inertia, torsional moments or forces arising from the transfer of the gas forces from the cylinder head to the crankshaft bearings.

Construction and materials used

The majority of engine blocks for small and medium size consists of a cast member, cast iron ductile iron ( for heavy duty ) and light metal ( mainly aluminum) find use as material. In some middle and almost all large engines, the engine block in two or more castings is separated because of casting problems. Most often, the cylinders are manufactured separately from the crankcase and been mounted with expansion bolts in this case. To circumvent the difficulties encountered with increasing casting size ( Thermal power stations and large marine propulsion ) are welded constructions of steel or cast steel preferred for most engines.

Other distinguishing features

Another distinguishing feature is the design of the engine block top surface, the so-called cover plate. Here a distinction is closed deck and open deck designs. In the closed-deck design of the water jacket surrounding the cylinder is closed at the top, there are so when looking up to the engine block only the cylinder bores and the engine oil and cooling water channel holes to see. In an open-deck block, the cylinders are detached, and the water jacket is open at the top, it is then sealed with a special head gasket through the cylinder head during assembly; A further object of the cylinder head is the fixation of free-standing and thus easily movable cylinder. Advantage of the closed-deck design is thus the slightly higher stiffness of the engine block, this is however the expense of a more complicated casting process.

Colloquially also the internal combustion engine of a motor vehicle is designated as a whole as " engine block ". Thus, the entire engine is meant as a unit, so the actual engine block, supplemented by the crank mechanism - namely, crankshaft, pistons and connecting rods with all the camps, as well as the cylinder head together with giblets. However, this is incorrect. The engine block without cylinder head and Nebenaggegate, but including all fixtures is called a short block.

Indicative of an engine block, the connection of the crankshaft bearing and cylinders. Very often, the engine block is the largest and most expensive casting of a motor vehicle. Often, only the oil pan is mounted beneath the cylinder block. The lower bearing of the crankshaft with individual bearing caps (cast or forged parts) and their bearing shells to count with the Engine Block: An engine block is not complete until he can hold the crankshaft and contains the cylinder.

Big Block and Small Block

Big Block and Small Block are coming from the U.S. designations to distinguish V8 automobile engines. Big block engines were produced almost exclusively by Ford, General Motors and Chrysler in the United States. The engines were installed in major American vehicles, but also muscle cars. Today Big Blocks are only sporadically present in large-displacement vehicles. Some pick- ups, American sports cars and trucks have this yet. At Big block the cylinder bore is usually greater than 4 inches.

The small block is no different from big block primarily by the size of engine, but by the dimensions of the engine block and the resulting space available for the combustion chambers (hole usually less than 4 inches). There are, for example, small-block engines with 7.0 liter engine ( Chevrolet Corvette Z06 ) and big-block engines with 5.9 liters of displacement.

The Chevrolet small-block engines have been continuously developed over the past 50 years and adapted to the requirements. GM celebrated in 2006 the 50th anniversary of his small block and has the hundred millionth small-block produces on November 29, 2011.