Engine body Description Crank mechanism Crankshaft Cylinder head The crankshaft is journaled in three main bearings The cylinder head is manufactured of specially alloyed cast iron. It is provided with replaceable valve seats for the inlet valves. ( MD2010 ), or four main bearings (other engines). The axial bearing on MD2040 consists of loose thrust wash- ers placed at the rear main bearing. On the other en- gines the rear main bearing cap is made of aluminium and serves as thrust washers. The crankshaft is statically and dynamically balanced and has induction hardened bearing surfaces.
At the front the crankshaft is fitted with a key joint and at the rear with a flange on which the fly- wheel is attached. The cylinder head is screwed onto the cylinder block with screws. The tightening of the cylinder head should be done in three stages. Cylinder block The cylinder block is cast in one piece of specially al- l oyed cast iron. Main and big-end bearings Pistons, piston rings The main and big-end bearings consist of steel shells li ned with bearing metal. The bearings are precision milled and ready for installation. Two oversizes are available as spare parts. The pistons are manufactured of a light-weight metal al- l oy.
They are fitted with three piston rings (chromium- plated) - two compression rings and an oil ring. Note: The thrust washers for the crankshaft's axial bear- i ng are not available in oversize. Camshaft The injection pump is driven from the front part of the camshaft by means of two or three separate cams (de- pending on the number of cylinders). Connecting rods The feed pump is driven via an eccentric cam from the rear of the camshaft. The connecting rods have I-sections. The piston bolt end i s through-drilled for lubrication of the gudgeon pin. Timing gears Flywheel The timing gears consists of cylindrical gears with be- velled cogs.
The flywheel is screwed on a flange on the rear of the crankshaft. It is statically balanced and fully processed. The starter ring is shrunk onto the flywheel. The camshaft and sea water pump are driven from the crankshaft gear via an intermediate gear. The engine's oil pump is built into the intermediate wheel and is dri- ven via this. Regulator weights are suspended in the front edge of the camshaft gear. A flexible coupling with damper element of rubber is screwed on the flywheel. The coupling transfers the force to the reverse gear/S-drive. 24