TM-9-2815-205-24 Technical Manual for M113 Engine 6V53 6V53T Download
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ENGINE SYSTEMS being one stroke and down being the return stroke. The air intake and exhaust functions are accomplished during the compression and power strokes as explained below. Scavenging The blower, which is an air pump that is gear driven from the crankshaft, forces air into the air box. Each cylinder has a row of ports in the cylinder wall opening to the air box and located at the bottom of the piston stroke. When the top of the piston moves down and uncovers the ports, air in the air box is forced through the ports. The air then flows toward the exhaust valves and produces a scavenging effect, leaving the cylinder full of fresh air when the piston returns and covers the ports. Compression As the piston continues the upward stroke, the exhaust valves close and the piston compresses the charge of fresh air. The fuel injector injects the required amount of fuel into the cylinder shortly before the piston reaches its highest point and continues into the power stroke. Power The heat generated from compression ignites the fine fuel spray to start combustion. Combustion continues until the injected fuel has all burned. The resulting pressure forces the piston downward on its power stroke. Exhaust When the piston is approximately halfway down, the exhaust valves open and most of the high pressure exhaust gases escape. Shortly thereafter, the piston drops below the inlet ports in the cylinder wall. Pressurized air is then forced through the cylinder. During this process, the remaining exhaust gases are removed (or scavenged) from the cylinder. END OF WORK PACKAGE TM 9-2815-205-24 0003 0003-3/blank