TM-9-2815-220-24 Maintenance Manual for AVDS-1790-2CA AVDS-1790-DA and AVDS-1790-2DR Engines Download
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TM 9-2815-220-24 THEORY OF OPERATION 0004 00 ENGINE COMPONENTS (Continued) Starter: The starter cranks the engine by converting electrical energy to mechanical energy. The starter is a heavy-duty, 24-volt, insulated, waterproof, fungus and corrosion resistant, solenoid-operated, enclosed shift- lever-type engine starter with 12 brush holders. The drive clutch is a heavy-duty overrunning type and the pinion clearance is adjustable. Turbosuperchargers: By compressing air to a density approximately two times atmospheric pressure, the turbosupercharger enables the AVDS-1790 engine to increase its power and efficiency without increasing its size or weight. The increased fuel economy also gives the vehicle a greater range. Exhaust gases from the engine cylinder combustion chamber drive the turbine wheel that is coupled to the compressor wheel on a common shaft in the turbosupercharger. As the exhaust gases turn the turbine and compressor wheels, ambient air enters into the center of the compressor wheel and flows radially outward. It increases in pressure and density while it is ducted into the engine intake manifold. Since the exhaust gases drive the turbine wheel, there is always a direct relationship between the power of the engine and the amount of air being delivered to the cylinders. The engine is supplied with all the air it needs to go faster because the increased exhaust gases drive the turbine and compressor faster. Conversely, as the engine goes slower, so does the compressor wheel. WP 0004 00-27