Does a fuel system need a return line?
When using a Return Style Fuel Pressure Regulator, it must be able to return 100\% of the fuel back to the tank. The return line should direct fuel close to the bottom of the tank and away from the pickup.
Can you block off a fuel return line?
Any fuel going through the return line is simply fuel your engine did not need/could not use. Blocking or restricting the line only increases fuel pressure at the injectors. Blocking the line results in the fuel pressure just being the maximum the pump can push.
Why do you need a fuel return?
It’s primary purpose is to return excess fuel from the carburetor to the fuel pump, however it serves other important functions as well. Aside from providing a path for excess fuel to return to the tank, the fuel return hose also prevents vapor lock and over pressurization from occurring within the carburetor.
Does a Holley Blue fuel pump need a return line?
The “blue” pump, P/N12-802-1, is rated at 110 GPH and it is designed for street/strip applications. These feature a gerotor pump design which is extremely efficient and quiet. Fuel pressure is pre-set at 15 PSI and both a pressure regulator and 3/8″ return line to the tank are required.
What happens if fuel return line is clogged?
If the fuel return hose becomes blocked or kinked it may cause the carburetor to flood from excessive fuel or pressure buildup. A flooded carburetor may cause engine stalling and hard starting until it is cleared, or enough fuel has evaporated.
Why does a diesel have a fuel return line?
Diesel has a return line because the fuel is injected via the Injectors. In a very dynamic and transient conditions, the load or need for fuel varies very radically. in that case the Diesel Injector may have extra quantity at a very high pressure due to the previous demand.
How much horsepower will a Holley blue pump support?
550 hp
They are rotor/vane-style pumps designed to flow high volumes of fuel at low pressures, perfect for low- to high-horsepower carbureted applications. The Holley Red pump flows 97 gph and supports 425 hp, while the Blue pump flows 110 gph and supports 550 hp.