Can you use a gas fuel pump on diesel system?

No, a gas fuel pump should not be used on a diesel system. The fuel pumps for gas and diesel systems are different and cannot be interchanged. The primary reason for this is the difference in fuel pressure requirements between gas and diesel engines. Diesel engines require much higher fuel pressure than gasoline engines, and running a gas fuel pump on a diesel engine will not produce enough pressure to properly operate the engine. Additionally, diesel fuel is denser and more viscous than gasoline, and a gas fuel pump may not be able to adequately move the diesel fuel through the system.