Which component is part of the engine oil cooling circuit?

Which component is part of the engine oil cooling circuit?

• A. Servo fuel heater
• B. Fuel pump
• C. Hydraulic reservoir
• D. Cabin pressurization controller

Answer: (A)

In the engine oil cooling loop, heat exchange often occurs with the fuel system to keep temperatures within safe and functional ranges. The servo fuel heater is integrated into that loop because it uses hot engine oil to warm the fuel that feeds the engine’s metering and control system. By placing a heater in the fuel path and tying it to the oil circuit, temperature stability is maintained for the fuel control unit, reducing icing risk and improving metering at cold starts and low temperatures. The other components listed belong to different systems—fuel pump to the fuel supply, hydraulic reservoir to the hydraulic system, and cabin pressurization controller to environmental control—so they do not participate in the engine oil cooling circuit.

In the engine oil cooling loop, heat exchange often occurs with the fuel system to keep temperatures within safe and functional ranges. The servo fuel heater is integrated into that loop because it uses hot engine oil to warm the fuel that feeds the engine’s metering and control system. By placing a heater in the fuel path and tying it to the oil circuit, temperature stability is maintained for the fuel control unit, reducing icing risk and improving metering at cold starts and low temperatures. The other components listed belong to different systems—fuel pump to the fuel supply, hydraulic reservoir to the hydraulic system, and cabin pressurization controller to environmental control—so they do not participate in the engine oil cooling circuit.