How Do Ford Dual Fuel Tanks Work? (Solved)

According to Global Industry Sales, GMC is currently the largest car manufacturer in the world. The company has been producing various models of cars since 1908, of which the Ford is one. A notable feature of this model is its dual fuel tanks.

You might be curious about how Ford dual fuel tanks work and why they are not used these days.

Dual fuel tanks work with two separate tanks (primary and secondary tanks). Although the two tanks offer benefits like they offer better weight distribution and more mileage, they cost too high compared to single tanks. Also, an extra tank creates more complexity because you need to maintain two different tanks.

However, this is not the full picture. Continue reading to know every necessary information regarding how dual fuel tanks work and what benefits or drawbacks they offer.

How Do Ford Single and Dual Fuel Tanks Work?

Dual fuel tanks were used in the past few years but single tanks have been out there forever. Here’s how single duel tanks work:

  • The fuel tanks have an electric pump.
  • There’s a DC motor that draws gasoline from the tank.
  • After that, the pump directs the fuel rail throughout the fuel line.
  • From the fuel line, the gasoline then gets into the cylinder where the fuel sparks with air and creates combustion.

In Ford vehicles, the dual tank system works in this way:

  • The Fords contain two fuel tanks; one is a primary and another is a secondary fuel tank.
  • There’s a connecting pipe between the tanks.
  • Fuel first moves to the primary tank and once the vehicle runs, the fuel moves into the secondary tank.
  • From the secondary tank, the fuel finally gets into the engine.

Here, a filler pipe, a vent line, and a discharge line work together throughout the process. Both tanks work separately but simultaneously. Another thing that the secondary tank does is replace the wasted energy of the primary tank.

Again, when the ignition is turned off or the speed of the vehicle drops below 120 ppm, the fuel pump becomes inactive. The powertrain control module mainly does this.

What Was the Original Concept of Dual Fuel Tank Implementation?

If we look at the older models, we can see that the smaller tanks were mounted on those trucks. This is because they were unable to carry enough fuel and did not have much mileage.

The main reason why Ford includes a dual tank system is:

  • To increase the fuel efficiency of its trucks. Small tanks are unable to carry enough fuel and did not have much mileage. And, this issue is dissolved by duel tanks as they carry more fuel and travel farther. When traveling long distances, the dual tank ensures that the engine does not shut down due to a lack of fuel in the path.
  • Dual tanks assist in the weight distribution of the trucks. Fuel weighs about 6.3 per gallon, so two tanks divide the weight. When it comes to a single tank, it causes a truck imbalance when the truck takes a hard turn.
  • Above all, dual tanks offer some backup fuel which might help in some cases.

Thus, the dual tanks have ensured vehicle rigidity as well as confidence and road safety. As in the case of single tanks, the fuel tank may fail in a place where there is no help in the vicinity. But this is unlikely to happen in the case of dual fuel tanks.

Model of Ford Dual Fuel Tank Technique 

At present we see both parallel and series systems in dual fuel tanks. In the parallel system, we see that the functions of the pumps running on two free fuel lines meet in the ‘Y’ connection in the fuel system. On the other hand, the series system sets the fuel pumps in a standard line.

However, models of dual fuel tank systems include the following components:

Fuel Pressure Regulator

A fuel pressure regulator uses a diaphragm when working. It controls the fuel compression caused by the fuel injector. The diaphragm of the regulator is driven by one pass of the tank and the other is connected to the vacuum in the intake manifold.

Fuel Reservoir

When there is less fuel in the truck and you fall into the extreme condition of the truck, the fuel reservoirs prevent the fuel barrier. Reservoirs are formed by fuel delivery assemblies and remain in-tank condition.

Venturi Jet Valve

When high pressure flows out of the fuel pump, the dual tank procedure removes it intending to start this venturi jet pump. This pump then pulls the fuel out of the tank to the assembly. 

This valve procedure sustains fuel allowance when a truck is upright and fuel levels are low. Also, its nylon filter system prevents dust from reaching the fuel tank.

Supply Check Valve

This valve unfolds when the pressure at the outlet of the pump surpasses the valve spring force tension. That time the engine shuts down, the valve shuts to regulate the pressure of the power line and to maintain the prime of the pump.

Shuttle Selector Valve

The main responsibility of a shuttle selector valve is to control the fuel pressure. Occasionally the pressure of the shuttle diaphragm exceeds the opposing spring force. This valve then opens a return line.

Why Did Ford Stop Including Dual Fuel Tanks in Their Vehicles?

Although single tanks have drawbacks like being small in size and offering a low carrying capacity, dual tanks had some bigger issues so the Ford company got back to the single tanks.

The drawbacks are:

  • The production cost of Ford dual fuel tanks was very high. The valve systems, automatic switches, and extra fuel pumps cost extra money.
  • It also took a lot of effort to maintain. 

On the other hand, building a big vehicle with a bigger tank was relatively cheap. So the Ford Company dropped the dual fuel tank system and introduced in-tank fuel pumps and larger tanks.

How Ford Dual Fuel Tanks System Works: Our Infographic

How Ford Dual Fuel Tanks System Works Our Infographic

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Ford implemented dual fuel tanks on their trucks, keeping in mind the concerns of its drivers. This initiative later became very effective for remote drives. The higher fuel capacity of the dual tank technique became popular among the drivers.

But due to high production costs and complex maintenance problems, Ford decided to shut down the dual fuel tank system. Larger tanks are currently mounted on all Ford models, except a few high-powered models. However, this article has told you why and how Ford Dual Fuel Tanks work.

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William Baldwin

This Is William Baldwin, The Founder & Managing Editor of this website. Me and my team share automotive tips, tricks, and news

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Talha Atta

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