Fuel and return lines

Yes, you will have the diesel spilling back from a higher pressure, but to a vented tank. Your 3ft 6in head of diesel is only equivelant to about 1.5psi so it will overcome that with ease.

Your engine fuel data says you have an electric lift pump that gives 3.5 psi so if the fuel self vents and recycles back to the tank when you switch on your pump will easily push it up to your tank.

If I am reading it correctly, once your engine is running your return line will overcome a head of 15" of Mercury, about 15 or 16 ft of water, or in this case about 18 to 20 ft of diesel, so you should not have a problem.

 

Thanks (breaths sigh of relief)