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Detailed description

Detailed description


Cylinder block

The cylinder block is made in one piece of special cast iron with cylinder barrels bored directly into the block. In the block are also drilled passages for the lubricating system.

Pistons

The pistons are manufactured from light alloy and have grooves for two compression rings and one oil scraper ring. The upper compression ring is flat and chromed, the lower compression ring is coated with molybdenum and has oil scraping properties, and the oil scraper ring is divided into three parts. The gudgeon pin is preshrunk into the connecting rod and so is not floating. An arrow on the top of the piston in the direction of the camshaft drive end indicates the fitting position.



Connecting rods

The connecting rods are forged with little end designed to receive a shrink-fitted gudgeon pin and exchangeable big-end bearing shells. This is achieved by making a laser cut notch across the hole and then using a press tool to split the big end. The hole is then machined to the correct size. This procedure provides a perfect fit between the cap and connecting rod.


Crankshaft

The crankshaft has ground and hardened bearing journals, providing a hard surface to protect against wear. The crankshaft is supported on five main bearings, where the middle one also acts as an axial guide bearing. There are drilled ducts in the shaft for the lubricant. All the main bearing shells are replaceable. The slotted ring included in the engine management system is screwed onto the crankshaft.



Cylinder head

The cylinder head is cast in light alloy and bolted to the cylinder head. Pentroof combustion chambers with 4 valves per cylinder have a centrally located spark plug. This improves the flow of gas into the cylinders and also the air/fuel mixture is burned efficiently. The engine is then given a high efficiency.