TUBE A NAT GAS 3N6910 - Caterpillar

Exhaust System
Exhaust gas flow restriction is created by a combination of the exhaust system piping, muffler or silencer and any system catalytic converter, scrubber or filter being used. Total system backpressure must not exceed 6.7 kPa (27 inches of H2O) at rated engine conditions. Excessive restriction causes reduced power, lack of engine response, excessive exhaust temperatures, and engine exhaust valve damage.Consult the Industrial Installation and Application Guide for details regarding exhaust system calculations before finalizing exhaust system design. Pressure drop (backpressure measured in kPa (inches of H2O), total equivalent length of exhaust piping in meters (feet), exhaust gas flow in cubic millimeters per minute (cubic feet per minute), inside diameter of pipe, and exhaust temperatures are used to estimate exhaust system back pressure.Maximum allowable exhaust system static bending load that can be carried by the turbocharger exhaust elbow is 27 N m (20 lb ft). If this bending moment is exceeded, provide a support.Fuel System
The connection points for both fuel supply and return are provided on the engine. Flexible connectors are recommended to accommodate relative engine movement during operation in the OEM machine.Fuel tank construction can be steel or aluminum. Fuel pump suction line should be located above the tank bottom to allow approximately 5 percent of the tank volume for sediment and water collection. A tank sediment drain valve should be provided, and a filtered tank vent is recommended to minimize dust in the fuel tank.The 3176B is equipped with a gear-type fuel transfer pump. In all installations, a primary fuel filter (such as a Racor filter) must be installed between the fuel tank and fuel transfer pump.A secondary Caterpillar fuel filter is used. This should incorporate the Caterpillar hi-efficiency 1R0749 Fuel Filter to protect fuel system injectors.Fuel Cooler Requirements
The 3176B electronic control module (ECM) is cooled by diesel fuel flowing to the engine. Fuel is routed from the fuel tank, to primary fuel filter, through the fuel transfer pump, to cored passages on the ECM, on to the secondary filter, to the injection pumps and finally back to the fuel tank. This fuel system incorporates a constant flow relief valve which returns approximately 4.2 L (1.1 gal U.S.) of fuel to the fuel tank per minute. Fuel temperature can increase approximately 16°C (60°F) to 21°C (70°F) as it flows through the engine. Fuel inlet temperatures at the fuel transfer pump must not exceed 79°C (175°F). If fuel temperatures consistently exceed this limit, a fuel cooler is required in the return fuel flow circuit. Higher temperatures will reduce the life of the electronic control module and decrease engine performance.Lubrication System
Engine Data Sheets provide oil system capacity, high and low sump levels, normal oil system pressure, and engine crankcase oil specifications. Some OEM installations require a modified oil level gauge due to engine installation angle or tilt. In these cases, it is an OEM responsibility to reestablish proper oil level markings for "add oil" and "full" indicators. Typical lube oil capacity is 30 L (32 qt) "full" and