COUPLING-ELBOW 9Y7058 - Caterpillar

Air/Fuel Ratio
The correct air/fuel ratio is important for the following considerations:
Achieving optimum service life for the engine
Control of emissions
Detonation Margin
Engine Performance
Environmental RegulationsIf the air/fuel ratio is not appropriate for the fuel and the operating conditions, a failure of the engine may occur. The service life of the turbocharger, the valves, and other components may be reduced.Any changes to the air/fuel ratio will affect the exhaust emissions. After adjustment, use an emissions analyzer to measure the exhaust emissions. Ensure that the engine is in compliance with local regulations for emissions.Site Installation Parameters
Site installation parameters will have a direct impact on engine performance and the ability to achieve optimum service life for the engine. The following parameters should meet Service Manual, "Application and Installation Guidelines"and Special Instruction, "Technical Data Sheet Requirements"for this product:
Fuel Pressure
Fuel Temperature
Air Supply Temperature
Inlet Air Restriction
Exhaust Restriction
Engine Room Pressure
Engine Room TemperatureInstallation Before the Fuel Control Valve
The fuel flows from the main gas supply through the fuel filter. Usually, the fuel filter is a component of the design at the particular site. The customer is responsible for supplying clean, dry fuel to the engine. The fuel filter may be supplied by Caterpillar or by the customer. To prevent particles from entering the engine, a 1 micron filter is required. The filter must be the proper size for the required gas pressure.The recommended location for the installation of the fuel filter is close to the engine but before the gas pressure regulator. Pressure gauges in the gas lines on each side of the fuel filter are recommended in order to monitor the differential pressure of the filter. A manual shutoff valve in the gas line before the fuel filter will facilitate servicing of the filter.The filtered fuel flows to the Gas Shutoff Valve (GSOV). The solenoid for the GSOV may be connected to the wiring harness of the engine or to a harness that is supplied by the customer. In either case, the customer may install a switch that can interrupt the circuit.The control system is configured for a GSOV that is energize-to-run. This means that the GSOV must be energized in order for the engine to run. To enable the fuel flow, the ECM provides +Battery voltage to the solenoid for the GSOV. The valve opens and the fuel flows to the engine. When the control system shuts down the engine, the voltage is removed from the solenoid. The valve closes and the fuel is shut off.Parallel Utility Applications
The fuel flows through the GSOV to the gas pressure regulator. The regulator may be supplied by Caterpillar or by the customer. A regulated pressure of 7 to 35 kPa (1 to 5 psi) is recommended. Less pressure may result in reduced power. More pressure may result in instability. The required stability for fuel pressure for parallel utility applications is 2 kPa (0.25 psi).Island Mode
The minimum fuel pressure for Island Mode is 20 kPa (3 psi). The required stability for the steady state fuel pressure for Island Mode is