OM 636 Technical Description
The OM 636 is a water-cooled, vertical diesel engine with a power rating of between 25 and 42 HP at maximum speed dependent on the fuel injection equipment fitted.
The cast iron crankcase has integral cylinders with a standard bore of 75mm. Re-boring is possible up to a maximum bore of 77mm. Pistons are available in 4 repair sizes. It is also possible to reline the block back to standard bore.
The injection pump and oil filter are located on the right hand side of the engine (as seen from the flywheel end). The generator, starter motor, oil dipstick and breather pipe are on the left. At the front, an alloy timing cover encloses helical gears driving the camshaft and injection pump off the crankshaft. A side cover seals the valve lifter chamber. The alloy oil sump is bolted to the crankcase.
The cast iron cylinder head is fastened to the crankcase by hexagon-head bolts. A composite cylinder head gasket seals the combustion chambers and water passages between the head and the crankcase. The cylinder head features removable precombustion chambers into which injectors atomize the diesel fuel for combustion. Pre-heater plugs are used as a starting aid. An alloy rocker cover with an oil filler seals the top of the cylinder head.
The 3-main bearing, drop-forged crankshaft has hardened bearing surfaces. The centre bearing serves as the thrust bearing. Counterweights on the crankshaft compensate for the rotational inertia in relieving the forces on the main bearings. The coolant pump is driven by a 'V' belt pulley fitted to the front of the crankshaft.
The forged steel connecting rods are equipped with bronze bushes at the small end to accommodate the piston pin and a 2- piece friction bearing at the big end. The bearing cap is secured to the connecting rod by 2 special bolts and nuts.
The alloy pistons generally feature 3 compression rings and 2 oil scraper rings. The floating piston pin is retained by circlips. The piston crown is dished.
The cast iron crankcase has integral cylinders with a standard bore of 75mm. Re-boring is possible up to a maximum bore of 77mm. Pistons are available in 4 repair sizes. It is also possible to reline the block back to standard bore.
The injection pump and oil filter are located on the right hand side of the engine (as seen from the flywheel end). The generator, starter motor, oil dipstick and breather pipe are on the left. At the front, an alloy timing cover encloses helical gears driving the camshaft and injection pump off the crankshaft. A side cover seals the valve lifter chamber. The alloy oil sump is bolted to the crankcase.
The cast iron cylinder head is fastened to the crankcase by hexagon-head bolts. A composite cylinder head gasket seals the combustion chambers and water passages between the head and the crankcase. The cylinder head features removable precombustion chambers into which injectors atomize the diesel fuel for combustion. Pre-heater plugs are used as a starting aid. An alloy rocker cover with an oil filler seals the top of the cylinder head.
The 3-main bearing, drop-forged crankshaft has hardened bearing surfaces. The centre bearing serves as the thrust bearing. Counterweights on the crankshaft compensate for the rotational inertia in relieving the forces on the main bearings. The coolant pump is driven by a 'V' belt pulley fitted to the front of the crankshaft.
The forged steel connecting rods are equipped with bronze bushes at the small end to accommodate the piston pin and a 2- piece friction bearing at the big end. The bearing cap is secured to the connecting rod by 2 special bolts and nuts.
The alloy pistons generally feature 3 compression rings and 2 oil scraper rings. The floating piston pin is retained by circlips. The piston crown is dished.