Fuel delivery systems have one common element that is at the center of every type of module assembly or in the tank hanger and that is the electric fuel pump. All electric fuel pumps operate on current from the vehicles battery or charging system to move fuel, under specific pressure to the carburetor or fuel injectors. There are three basic electric fuel pump types:

Turbine:

An armature located inside the fuel pump case operates a turbine blade, which turns at high speed to create and maintain the pressure needed to function correctly. The fuel is skimmed from the spinning blade and directed into the outlet of the pump. These turbine type pumps are typically used on multi-port fuel injected vehicles. Although the operating pressures of this type of pump are similar to other styles, closer tolerances make it sensitive to fuel contamination such as foreign particles and other outside influences.

Gerotor:

As the name indicates, the gerator is a gear drive pump, which also uses an armature to drive a smaller gear that in turn drives a larger outer gear. Because of the precise gearing, gerator style pumps are quieter when operating. The rotation of the gear creates both vacuum drawing fuel into the pump and a contraction that forces fuel out of the pump. This type of pump is also used on multi-port fuel injected vehicle such as ones used by Ford and Chrysler. Similar to the turbine design, gerator type pumps are sensitive to fuel contamination.

Rollervane:

While all of the stated types of pumps use an armature, the roller vane pump drive metal rollers that are fitted to a rotor. A vacuum is created by the rollers that pull fuel into the pump while the driven rollers also force the fuel from the pump chamber under pressure. These types of pumps can tolerate more fuel contaminates, but the trade off is that they are noisier than the turbine and gerator type pumps. You will find rollervane pumps also used in multi-port fuel injected applications.

Typical Module Designs

Most vehicle manufacturers use in the tank module assemblies, which are made of fuel resistant plastic. Autobest Module Assemblies are built under strict guidelines to meet or exceed manufacturers’ requirements. Because we are an O.E.M. supplier, we realize that the quality in raw materials and design results in higher performance and durability.

What makes up a Module Assembly?

Ø       The Reservoir – A plastic molded fuel-resistant body. It holds gasoline to ensure

that there is fuel available during all operating conditions. Think of it as a tank

within the gas tank.

Ø       The Strainer – A filter located outside the module assembly ensures that the

gasoline inside the module has been filtered or “strained” prior to being delivered

to the engine. Some applications have two strainers one outside and one on the

inside of the module. The strainer on the inside is not a serviceable component of

the module assembly.

Ø       The Fuel Pump – The electrical component that operates by sending fuel under

pressure to the engine.

Ø       The Float – A component that is attached to measuring device that indicates the

fuel level in the tank.

Ø       The Sender Unit – Works with the float and controls the fuel gauge inside the vehicle.

Ø       The Spring –Expands inside the gas tank based on operating temperatures keeping the reservoir at the bottom of the tank.

The fuel pump creates pressure within the fuel lines to ensure that there is a constant flow and no interruption of fuel to the fuel injectors or carburetor. Because of varying driving conditions such as area that are dusty or prone to severe conditions, strainers are part of the module assembly. Even to best strainer cannot keep all particles out of the fuel system but, not having one gives virtually no protection from foreign particles of be ingested by the gasoline engine.

Typical Hanger Designs

The design of fuel pump Hangers shares some of the same characteristics of the module assemblies. Although Hangers are more simplistic in comparison, they operate to serve the same basic function.

What makes up the Hanger Assembly?

Ø       The Metal Hanger – The base that holds and secures the other component

securely. It is mounted at the fuel tank either at the top or on the side depending

on the application.

Ø       The Fuel Pump – Is mounted to the metal Hanger to which the inside the tank

fuel lines are attached at one side and the strainer is at the other side.

Ø       The Reservoir – Keeps an ample supply of fuel and located below the fuel

pump assembly. As in the module design, ensuring that there is a constant

supply of gasoline available in low fuel conditions and during sharp turns is the

primary purpose of this design.

Ø       The Strainer – The filter, which “strains” the fuel prior to being drawn into the fuel pump assembly.

As with the Module Assembly, strainers are an essential component of the Hanger Assembly and should always be replaced when installing the hanger. Failure to do so will void the warranty on the Hanger Assembly. This simple practice will save time and aggravation down the road.