Engine with fuel flowmeter in pump inlet - returns excess fuel downstream of meter after cooling to avoid temp. affecting reading

摘要

The arrangement is intended for measuring the momentary fuel consumption of an engine (M), particularly in a motor vehicle. It comprises a fuel line (3) which returns excess fuel from the engine to the fuel pump (P) inlet at a point downsteam of a flowmeter (4) which thus only measures the actual consumption. In order to eliminate the effect on the measurement of the temperature difference between the return flow and the flow (5) direct from the fuel tank (1), the return flow is cooled (7) before it reaches the pump inlet, preferably by heat exchange with fuel in the tank.