How to Convert Any in Tank Electric Fuel Pump to an External Inline Pump




Introduction: How to Convert Any in Tank Electric Fuel Pump to an External Inline Pump

About: Lateral thinker, Originator of Inclined Bed Therapy (IBT) Originator of Pocket Full Of Acorns Project. Originator of Operation OASIS.

Cost: £35.00

This video shows how an in-tank electric fuel / diesel pump can be modified to keep the existing fuel gage / sender unit and remove the faulty intank pump, replacing it with an easy accessible in-line fuel pump.
Many vehicles, including my Citroen picasso are fitted with an in-tank fuel pump. And inevitably are prone to failure, especially if you are running waste vegetable oil mixes or bio fuel. These pumps often have two filters in the tank that are prone to clogging up even when run on pump diesel. Have road tested car today it runs great, more power than with the original manufacturer pump. Check out my Channel for more interesting videos.

Hope you find this video helpful, if you do don't forget to give it a thumbs up and share and who knows, I might even get my £35 back off the advertising :P

Rant: Citroen Picasso Fuel Pump Nightmare ended. Citroen in their infinite wisdom decided that putting a fuel pump which is prone to packing up inside the fuel tank, which means you have to jack the car up, put it on stands, drain the fuel, remove the exhaust heat shield, move the hand brake cables, remove the four bolts, remove the rubber filler pipe hose, remove the pipes and unplug the cables. Then you have to pull the tank out enough to remove the fuel pump. Or pay a garage to do same. Reassemble having forked out £125 for a new pump only to find the new pump lasted around 2 years before it too gave up the ghost. That poxy tank had been removed no less than six times, involving cleaning the pump filters, and hoping above all hopes that the pump would run and it did for a few miles, then braking down again and again. Well enough was enough. I removed the old pump which also includes the tank fuel gage gizmo. Threw the pump away and secured a steel rod with cable ties to hold the pipe on the bottom of the pump. Inserted the pump-free sender unit. Refitted the fuel tank, cut through the main fuel pipe and fuel pump wires and fitted a 3 bar external pump that works like a dream. Never again will I have to remove the fuel tank and if this pump packs up which I doubt, it will take 10 minutes to change and cost a mere £35.00. Up Yours. Citroen.

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Step 1: Jack Up Your Car to Drain Tank and "ALWAYS" Support Car With Axle Stands.

1. Never crawl under a vehicle supported by an hydraulic jack. Always use axle stands or ramps under wheels.

2. You will need to siphon off the majority of your fuel. If you have the new external pump already, this can be used by running two wires to your battery terminals, connecting positive to positive and earth to negative. Secure length of tubing to pump and insert into tank. Connect wires to transfer fuel to several 20 litre containers with screw capped lids for safe storage.

3. Cut a 20 / 25 litre plastic container open on one side as per picture. This will serve to drain excess fuel

4. Slide your drainage container under tank and unscrew filler hose jubilee clip, easing rubber pipe off to afford the remaining fuel to be drained. I know it should be obvious but don't smoke or have any naked flames or anything that can cause a spark near the fuel being emptied.

Step 2: Remove All Bolts, Wires, Cables, Exhaust Shield and Pipes From Tank

The Citroen Picasso tank has 4 bolts, 2 on the centre bracket that crosses the middle of the tank and one at each end. First remove the exhaust heat shield and pull the hand brake cables out of the holders, remove wiring clips and pipe clips and remove filler hose completely one drained. Place drainage container back under bottom hose coupling. Remove all 4 bolts and ease towards filler end of tank by pulling and raising far end with your foot so it can be eased out and down, taking care not to kink any pipes. Once lowered the wiring connector and the two fuel pipes can be removed.

Then unscrew plastic collar that holds fuel pump in place. This unscrews anti-clock-wise. Use a long screw driver to leaver the collar around if it can't be moved by hand.

Step 3: Make Sure Your New Fuel Pump Delivers Correct Pressure

The Citroen Picasso 2 litre HDI requires a 3 bar pump to open the pressure sensor. This is essential for the vehicle to run. The pump shown is wrong for this vehicle, but can be fitted to other vehicles. This type of pump is noisy. The correct pump is shown secured to the vehicle. This one delivers 3.5 bar and works well with the Picasso.

Step 4: Remove Wiring From the Pump, and Remove the Pump From the Plastic Cage That It Sits In.

Remove wiring from the defective in-tank pump, taking note of live and earth / negative colours.

Remove the defective pump from the plastic housing cage that it sits in and cut off or pull off the plastic hose from the bottom of the old pump as shown.

Step 5: Insert a Steel Rod With Cable Ties to Hold Flexible Pipe Close to Bottom of Tank

Cut a length of stiff steel wire so that it is slightly shorter than where the old pump was sited at the bottom of the sender unit / pump housing. Secure with cable ties as shown, to the plastic housing.

Allow sufficient hose to bend at the bottom of the pump reservoir / housing. This will allow fuel to enter freely as we don't want the end of the pipe becoming blocked by being flat against the bottom of the housing.

Once secured the metal rod will need to be bent so that it slides into the pump housing with ease.

Step 6: Reassemble Fuel Sender Unit / Pump Housing

Check that the end of your fuel pipe is secured with cable ties nice and tight and protruding below the level of where the old pump used to rest as shown.
Push pump housing back inside sender unit / fuel gauge housing until it clicks into place and fit the unit back inside the tank taking care to keep rubber gasket in position. Tighten firmly by hand and reconnect pipes and cable connector.
Re-fit tank back to can in reverse order of it's removal.

Step 7: Expose the Wires by Peeling Back Outer Protective Cover. Cut the Two Pump Wires That We Identified When We Removed the Pump.

In the Picasso these are obvious due to being thicker than the fuel gauge wires. Grey was live and green and yellow was the earth in this case. Cut the wires far enough down the loom to leave plenty of wiring to connect to the pump.

Crimp on two spade end connectors to the ends of the cut wires.

Step 8: Fit Your New Pump, Seurely to the Bodywork Under the Vehicle or Inside the Boot.

In the picasso, the first pump was fitted as shown by bending the brackets so that it could be bolted onto an existing 10mm stud and a convenient hole to take a self tapping bolt.
The larger of the two fuel pipes was cut and the ends fitted to the new pump secured with cable ties. Loose pipe was also tied up using cable ties. The pump was located in a convenient recess in front of the tank. The existing stud and hole suggest an external pump must have been fitted originally and the in-tank fuel filter and sender unit fitted as an after thought by the manufacturer.

As it happens, this first pump worked perfectly but the car would not start due to the pump not putting out sufficient pressure to open a sensor that required 3 bar pressure.

Step 9: The Correct Pump Required a New Bracket So I Made One

Using a short length of 22 mm copper tubing, which was hammered flat and formed around a branch in the vice as shown. The vice was used to close the bracket tightly around the branch which was approximately the same size as the pump.

Do not use the pump for this purpose as you will inevitably damage it.

Once formed, the bracket was cut with a hacksaw as shown and a hole drilled to take the 10 mm stud located next to the tank.

Step 10: Correct Fuel Pump Now Installed, Wired and Connected to the Fuel Pipes Car Now Running.

Insulation tape was wrapped around the pump to prevent vibration and noise and the fabricated copper bracket was fitted under the car as shown, fuel pipes were connected. The outlet pipe on the pump "Not the side shown" had to be warmed with a hair dryer and gently persuaded to bend to fit the new pump.

It is worth noting the positive and negative terminals on the new pump because you can't see the symbols once installed.

Silicone was used to reduce vibration by easing the pump and bracket forward and using a caulking gun to squeeze plenty between the pump and the body on both sides. This will also help to cut down noise and provide bonding of the pump to the car underside, "not that it needs it".

Refill tank with 10 litres of fuel and carefully check for leaks.

If all goes well, your tank fuel gauge now works properly and your new pump will work very well. It will make slightly more noise being outside of the tank but if it ever fails, it will cost around £35 to replace as opposed to £133.00 from Citroen, it will take about 30 minutes to change instead of half a day or longer when you have to remove an int-tank pump as you now know :) Hope this video helps someone to avoid having to change in-tank pumps which are prone to early failure as I found out.

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    6 Discussions


    5 years ago

    In our family, any car with less than 10 years and 100K miles is considered new. Unfortunately most cars today use in tank fuel pumps. I'm glad to know that there is a way to change it.


    Reply 3 years ago

    Yes, I know the 10 years young rule only too well :)


    8 months ago

    It’s great to know it would only take 10 minutes to change because you’ll most likely have to change it once a month or so without a filter in the tank to stop debris from getting sucked into the pump.


    11 months ago

    I have a 99 explorer 4.0 intake want to put a electric fuel pump outside how to do it


    3 years ago

    will that work on a fuel injected engine


    Reply 3 years ago

    The picasso is fuel injected.