* Pressure Regulation: The fuel system uses a fuel pressure regulator to maintain the correct pressure for the fuel injectors. A secondary pump, without the regulator in the circuit, will likely over-pressurize the system, potentially damaging injectors or other components.
* Return Line: Fuel injection systems typically use a return line to send excess fuel back to the tank. Bypassing the original pump and the return line with an external pump could lead to fuel overflowing in the system.
* Safety Mechanisms: The fuel pump is usually integrated with various safety features (e.g., pressure sensors, low-fuel indicators) that are bypassed if you use an external pump.
* Potential for Airlocks: Introducing another pump and lines can easily introduce air into the system, causing difficult-to-resolve starting issues or even engine damage.
To transfer fuel from the tank, you'd need to use a method designed for safely siphoning or draining fuel, rather than trying to force it through with another pump. Improperly handling fuel is very dangerous, so it's crucial to use appropriate safety measures.
