3.0 Fuel Injection 121

We explore the five varieties of fuel pumps in TCM fuel-injected engines. One basic pump handles naturally-aspirated engines with two adjustments for fuel pressure.Here's a detailed diagram of the pump assembly, showing key components like the vapor ejector, fuel inlet, and relief valve, essential for understanding its operation.The latest IO-550s feature a third pump type with three adjustments, including altitude compensation. We also have special pumps in 240- and 360-series engines where the metering valve is integrated.Let's look at this cross-section of a fuel pump. Notice the intricate internal mechanisms and connections that regulate fuel flow and pressure, crucial for engine performance.This schematic illustrates another pump design, highlighting the drive shaft, vapor separator, and adjustable orifice. Each part plays a vital role in fuel delivery to the engine.This slide details the fuel control assembly, which includes crucial components for precise fuel management within the engine system.The fuel control assembly contains manual mixture and fuel metering valves. These rotary valves connect to cockpit control levers for precise adjustments during flight.We illustrate mixture valve positions: idle-cutoff routes fuel back to the pump inlet, lean settings partially uncover the metering jet, and full-rich directs all fuel to the jet.As fuel flows past the mixture valve and metering jet, the fuel metering valve precisely regulates the amount of fuel delivered to the manifold valve, advancing with the throttle.We examine the differences in fuel injection systems. RSA relies on both air and fuel forces for pressure differential, while Teledyne-Continental uses a special pump to produce metering pressure.