86 Bronco II Fuel Pumps

[The Slider]

I know the 86 Bronco II has 2 fuel pumps... Is there a way just to have ONE fuel pump instead of the two?

Thanks!
Chaz

 

[wildbill23c]

There's a low pressure pump in the tank and a high pressure pump in the frame rail. Not sure if one would be able to do the job or not. I've never tried using just the frame rail pump, don't see where it would work very well with just 1 pump, maybe if you got a larger high pressure pump?

 

[Spott]

I know the 86 Bronco II has 2 fuel pumps... Is there a way just to have ONE fuel pump instead of the two?

Thanks!
Chaz

The only simple method to have 1 pump instead of two for that engine, is to use a carbureted engine instead of a fuel-injected engine. In fact, that's how Ford first designed the 2.8l Cologne V6.

When they changed it to a fuel-injected design, they needed more fuel pressure at the engine. Rather than redesign the fuel delivery system entirely, they instead added an in-line "booster pump" under the cab. However, this design is reliant on the original "lift pump" in the tank. The booster pump cannot draw fuel out of the tank by itself, reliably, and the lift pump cannot generate enough fuel pressure to run the engine.

Later designs changed to use a powerful enough pump in the tank to pressurize the fuel system, but they also increased the pressure specification for the fuel system almost double, and eliminated the 2.9l engine design as an option. If you put one of those pumps in your tank, it would do a whole lot of work to push a whole lot of fuel, most of which would get returned to the tank by the pressure regulator.

If you looked up the flow rate and pressure rating of your current pump system, and found an in-tank pump with similar numbers that is also the same length and mounting as your current pump, that should serve your purpose. You will also have to install a check-valve in the fuel line where the booster pump was located, because the booster pump includes a check-valve internally. Without the check-valve, you will have to crank your engine significant longer before it will start.

 

[alwaysFlOoReD]

I had a b-2 that the previous owner installed a 4.0 into. He used a [IIRC] mustang in tank high pressure 40 psi pump in the original b-2 tank. There was some filing done so the keys of the pump would align. The frame pump was deleted. Sorry, I don't have any further details.

 

[The Slider]

Good to know..

Thanks everyone!

Chaz

 

[adsm08]

The easiest way to do this that I know of is to get a fuel pump (just the pump, not the whole sender unit) for an 89 or 90. Then you drop the tank, replace the pump on the sender assembly, and find some way to patch the hole your HP pump leaves in the line when you remove it.

If you can find a whole 89 or 90 B2 and get the fuel lines back to the tank that would be the best way to deal with that.

You can't just use the whole sender or your gas gauge won't work.

 

[wildbill23c]

The only simple method to have 1 pump instead of two for that engine, is to use a carbureted engine instead of a fuel-injected engine. In fact, that's how Ford first designed the 2.8l Cologne V6.

When they changed it to a fuel-injected design, they needed more fuel pressure at the engine. Rather than redesign the fuel delivery system entirely, they instead added an in-line "booster pump" under the cab. However, this design is reliant on the original "lift pump" in the tank. The booster pump cannot draw fuel out of the tank by itself, reliably, and the lift pump cannot generate enough fuel pressure to run the engine.

Later designs changed to use a powerful enough pump in the tank to pressurize the fuel system, but they also increased the pressure specification for the fuel system almost double, and eliminated the 2.9l engine design as an option. If you put one of those pumps in your tank, it would do a whole lot of work to push a whole lot of fuel, most of which would get returned to the tank by the pressure regulator.

If you looked up the flow rate and pressure rating of your current pump system, and found an in-tank pump with similar numbers that is also the same length and mounting as your current pump, that should serve your purpose. You will also have to install a check-valve in the fuel line where the booster pump was located, because the booster pump includes a check-valve internally. Without the check-valve, you will have to crank your engine significant longer before it will start.

I don't think the 2.8L V6 had an in tank fuel pump, just the one on the engine block.

 

[alwaysFlOoReD]

I don't think the 2.8L V6 had an in tank fuel pump, just the one on the engine block.

1986 would have the 2.9l.

 

[IIBRONCOS]

Unless there are fuel parts missing, having 2 fuel pumps shouldn't be a problem. The high pressure frame rail pump is easily accessed, and cutting an access panel in the cargo area makes the in tank pump/sending unit easy to get to.

 

[wildbill23c]

1986 would have the 2.9l.

I was referencing someone's post regarding the only way to get 1 fuel pump would be to use the 2.8L V6 which is carbureted and in fact only has 1 fuel pump and its on the driver's side of the engine block.

 

[alwaysFlOoReD]

I was referencing someone's post regarding the only way to get 1 fuel pump would be to use the 2.8L V6 which is carbureted and in fact only has 1 fuel pump and its on the driver's side of the engine block.