TM 9--2815--247--34 0004 00--12 THEORY OF OPERATION -- CONTINUED 0004 00 CRANKCASE BREATHER AND FIRE EXTINGUISHER SYSTEMS Crankcase Breather System  A large diameter breather tube is run through the engine from the top of the damper housing to the back of the engine (Figure 1--12). The engine breathes from the top of the damper housing. The engine is shipped with a breather extension tube to facilitate connection to the RH bank turbo tail pipe. At the bot- tom of the extension tube is a small trap where oil drains to the RH bank corner of the oil pan. Fire Extinguisher System  The engine is equipped with a fire extinguisher tube located in the “V” (Figure 1--12). This tube is connected to the engine compartment fire extinguisher system. The tube has small holes drilled along the entire length to direct the carbon dioxide (CO₂) fire extinguisher fluid in predetermined directions around cylin- ders, fuel metering pump, and inter--cylinder components in case of fire. FRONT SHROUD TO AFTERCOOLER BYPASS VALVE HOUSING 0.030 IN. RESTRICTOR PLATE BETWEEN BREATHER TEE AND ACCESSORY DRIVE HOUSING FROM CRANKCASE AND ACCESSORY DRIVE HOUSING REAR SHROUD TO LEFT EXHAUST PIPE REAR CRANKCASE BREATHER TUBE FROM CRANKSHAFT DAMPER AND OIL FILTER HOUSING FUEL RETURN TO VEHICLE FUEL TANK FIRE EXTINGUISHER TUBE TO AFTERCOOLER BYPASS VALVE HOUSING CRANKCASE BREATHER DRAIN CRANKCASE BREATHER TUBE CRANKCASE BREATHER TUBE TEE FUEL METERING PUMP FUEL CUT--OFF LEAD FUEL METERING PUMP FUEL METERING PUMP FUEL CUT--OFF CONNECTOR Figure 1--12. Engine Crankcase Breather, Fire Extinguisher System and Fuel Return