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Fuel Pump & Tank Removal DIY: 850, S70 & Gen 1 V70

Red-Arrow » Well some of you know I had a gas leak from some place above the tank. When filling the tank up to the max without spilling fuel I would get a fuel smell and noticed the side if the tank getting wet with fuel.

OK so first we removed the rear bench seat and push into place the rear bench seat, this gives as access enough to unbolt the 5 nuts holding down the cover. We then unclip the 3 looms that feed the fuel pump, sender unit and pressure sensor? These looms must be disconnected before the bolts can be undone to drop the tank.

fuel pump wiring looms.
fuel pump wiring looms.


The looms connect to the side of the car just under the passenger rear seats.

Wire location
Wire location

We then jack the car up and use an axle stand for safety.

First we open the fuel flap and undo the two torx screws which hold the filler neck in place.
Now we can unbolt the two metal tank straps that secure the tank to the under body. We do not undo the third bolt where the two straps meet. The tank straps are very flexible and will allow lots of movement to pull the tank down and back.

The tank will fall as soon as the last bolt comes out so. There is no danger of breaking the fuel connectors of hoses as there is lots of flex thankfully.
Tank drop

Tank drop
Tank drop

I was not able to take a picture of this stage because I made a Royal frigging mess! I was not about to touch the camera with my oil foam stained hands! The important part for testing leaks is using the EVAP hose that connects to the roll over valve. I disconnected this pipe and connected it to a bicycle pump and slowly began to push air into the tank. In this picture the pump has already been removed so imagine its still in there.

EVAP roll over valve
EVAP roll over valve

 I realised I miss a few good pictures so I’m trying to show you what places to test for leaks.

I understand the heat shield can be a problem so check the mounts for them as well.

Fuel pump and test areas
Fuel pump and test areas

To remove the fuel hoses you simply lift the connector body up which some how allows the o-rings to slip off the barb. If you pull on the pipe you will end up breaking something. This is a simple part but I can see how somebody would make a mess of it.

fuel pump ful hose connector
fuel pump ful hose connector

I discovered that none of my hoses leak but the fuel pump itself was the cause of the leak, it has a rubber seal with a lip that can be caught and folded if not seated correctly. I looked at the cars history and the fuel pump was replaced a few years ago. Who ever replace the electric motor did not seat the seal and as a result the car has been leaking gas for years.

The electric motor cannot be service, it is a 100% sealed unit I discovered. I really took it apart for the sake of curiosity.

This is a series of pictures that show the stages of deconstruction .

pump1
pump1

FUEL PUMP & TANK REMOVAL DIY

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