Diesel fuel return line purpose

I pulled this fitting and I can see completely through it and blow air both directions. In fuel systems with a return line the fuel pump is continuously pumping gas through the fuel system at a much higher rate than is actually needed.

Adding a return fuel line is an essential part of your electronic fuel injection installationEFI systems require a return line to move unneeded fuel from the fuel injection system back to the fuel tank.

Diesel fuel return line purpose. As others have mentioned there is a set of different functions that the return line provides one of which is a pressure over flow port so that the fuel has some place to go when it gets too much pressure and is released back to the tank. Another function that the diesel fuel provides is cooling. Diesel fuel serves multiple functions when the engine is running more than just providing a flammable fuel for combustion.

It also acts as a lubricant and coolant for the extremely close-tolerance parts inside your injectors and injection pump. In many comman rail deisel fuel systems the fuel coming out of the return line is very hot. So the return line is often sent back to the tank.

A fuel tank is there to store fuel but another fuction of the fuel tank is to allow the fuel to cool down through a combination of mixing with the fuel still there. And the tank looseing heat to the atmosphere. In fuel systems with a return line the fuel pump is continuously pumping gas through the fuel system at a much higher rate than is actually needed.

This keeps gasoline in the fuel lines cool and flushes out any vapor bubbles that might form. This prevents vapor lock in your fuel system. The fuel return from the injection pump and the leak-off from the injectors is often returned to the filter on European vehicle systems as a means of warming the filter for cooler climate operation.

Increased temperature reduces the density of the diesel fuel. Since a constant volume of fuel is injected on each stroke the reduced density means that a smaller mass of fuel is available to be burned affecting the stoichiometry of combustion and also reducing engine power. Increased temperature reduces the viscosity of the diesel fuel.

Adding a return fuel line is an essential part of your electronic fuel injection installationEFI systems require a return line to move unneeded fuel from the fuel injection system back to the fuel tank. This process of cycling fuel from the tank to the injectors or throttle body and back to the tank is a complex process. Consider when lots of fuel is trying to go down the filler hose - air has to escape from the tank to allow the fuel to get into the tank.

The breather provides a return line for that air to escape. It is said to reduce misfiring and knocking from the engine. Its also effective in removing excess moisture from the fuel line.

This chemical really helps when there is old gas in the fuel tank thats just blocking the fuel line and not burning. PEA is added to the injector cleaners so. The fuel that runs through them is of a low pressure and it is not always noticeable when these perish but they can introduce air when the engine is off.

This can cause long cranking times when starting attributed to the diesel draining back to the tank. On a cold start the fuel then has to be drawn up the pipes again to the engine. In this video I will show you how to replace old leaky Diesel injector return lines that can cause performance issues and a messI have mentioned in the vide.

Workings of the Diesel Return Flow Sensor RFS400. In a common rail diesel engine a high pressure fuel pump supplies diesel fuel to all injectors. When fuel inside a cylinder is required the motor management system will open the injector of that cylinder to inject the required amount of fuel in the cylinder.

The l eakage oil line ensure optimum performance and can withstand high temperatures. To better serve the usage for conveying fuel in cylinders diesel leakage pipe proved to be an optimal choice because of its design and quality which can withstand. I was putting a return line cap and o-ring kit on my truck.

I have been having problems with air in the fuel system. Please correct me if I am wrong but the check valve in in the brass fitting where the return line goes into the fuel filter head. I pulled this fitting and I can see completely through it and blow air both directions.

Every fuel line experiences pressure loss depending on fuel line length and fuel flow rate. It should be noted that fuel lines which feed pressure gauges experience the least amount of loss as the flow rate through the gauge line plummets to near zero flow levels. There is a main fuel line from the fuel tank to the fuel rail.

Also a return fuel line from the fuel pressure regulator. This return line is located downstream of all the injectors. Most fuel pressure regulators use a diaphragm and spring combination within its housing.

Also with a vacuum source on the top side of the diaphragm. This is to counteract the spring pressure. When high demand dictates.

The fuel oil system for a marine diesel engine can be considered in two partsthe fuel supply and the fuel injection systems. Fuel supply deals with the provision of fuel oil suitable for use by the injection system. This line also incorporates a flow alarm.

They must also be self closing to stop the return of atmospheric air to the. Marine Diesel This is a distillate fuel that boils at a higher temperature than gas oil. The fuel varies from ASTM No.

2 diesel fuel to ASTM No. The composition can vary within the following range. 2 diesel fuel No.

2 that is contaminated with heavier fuel in the bottom of the tanker and. IP liquid fuel pressure opens the check valve to allow fuel to the return line which fills the injectors when the IP pressure drops with engine shut down the spring loaded check ball closes seats preventing any fuel in the return line going back into the IP.