Operation CHARM: Car repair manuals for everyone.

A. Replacing Fuel Tank

Special Tools: J-41031-A (replaces 9512614-0), 999 5011-5, 999 5485-1

Warning!
Do not smoke or have anything in the area which can ignite or cause sparks.

AA1

Draining fuel system

Preparations





Drain the fuel tank using fuel pressure adapter hose J-41031-A, see Special Tool Bulletin 97; 5/96.

Drain fuel line and fuel filter according to BA. Replacing fuel filter (B).

Drain fuel tank according to: AA3 or: AA5.

AA2

Replacing fuel tank

Remove and lower:

- Rear suspension, fuel tank according to See other manual: (Service Manual: Section 4(43,46), AWD, 850 1997-).

AA3

Draining fuel tank, alternative 1:





Fuel pump (FP) working

This method will take a long time to drain the fuel tank if starting with fuel tank full.

If the tank is not completely full, move fuel from the left to right halves of the tank by driving in a tight left-hand circle.

This will reduce drainage time as the electrical fuel pump (FP) can pump fuel more effectively from the right half of the tank.

To use the fuel pump (FP) without having the engine running, connect 12 V to the fuel pump (FP) connector.

Make up adapter wiring and connect this to the fuel pump (FP) connector in the luggage compartment.





The fuel pump (FP) connector is a 2-pin gray minitimer connector "D", as illustrated. The red cable is positive and the black cable negative.

Pump out fuel using fuel pump (FP) with fuel draining unit connected.

The right half of the tank, where the fuel pump (FP) is located will be drained first.

Check the levels as follows with an ohmmeter connected.

Check as follows: Allow the pump to run for a time, the fuel draining unit will then shut off and the pump will pump fuel from the left to the right halves of the tank with the ejector. At the same time check the levels.

Check the levels in the two halves of the tank by measuring the resistance over the two level sensors.





Disconnect the two black connectors "A" and "B1" in the luggage compartment as illustrated.

AA4





Connect two ohmmeters using the adapter wiring. Connector "B1" must be short-circuited with a jumper. Make up a jumper using a 2-pin minitimer, as illustrated.

Connect an ohmmeter to "B2" to check the left half of the tank.

Connect the other ohmmeter to connector "A" to check the right half of the tank.

If connector "B1" is not jumped with "C" the resistance over connector "A" cannot be measured.

The resistance of level sensors and the levels in both halves of the tank can now be checked.

When the fuel tank is empty resistance is:

160 ohms

for the sensor on the fuel pump (FP) unit, connector:

"A".

167 ohms for ejector unit sensor, connector: "B2".

When the fuel tank is full resistance is:

5 +/- 2,5 ohms per sensor.

Check the levels in the left and right halves of the tank.

If there is fuel left in the left half of the tank, shut off the fuel draining unit and valve at the fuel rail before the right half of the tank is completely empty.

Run the fuel pump in order to pump the remaining fuel from the left to right halves of the tank using the ejector.





The level in each half of the tank can be read off using the two ohmmeters connected as illustrated.

Hint: Ensure that the fuel level in the left half of the tank is always lower than in the right half of the tank by checking the levels using the ohmmeters.

AA5

Draining fuel tank, alternative 2:

Fuel pump (FP) not working





First check the fuel level in the fuel tank.

If the fuel pump (FP) is not working the rear axle and fuel tank must be lowered according to: AA2.

Then the fuel tank can be drained as follows.

Tip the fuel tank up a little so that the pump and ejector openings are at the top.

Remove all fuel lines according to: AA6.

Expose wiring to each unit.

Unscrew collars using tool 999 5485-1 and remove pump and ejector units.

Screw on nuts again.

Note
The collar must always be reinstalled. Otherwise the tank pipe will swell and the collar will be hard to install causing leakage.

Warning!
Do not smoke or have anything in the area which can ignite or cause sparks.

Pump fuel out of the right and left halves of the tank with an open hose connected to the fuel draining unit.

AA6

Replacing fuel pump (FP) or ejector with the rear axle lowered and the fuel tank drained.

Remove:

- Fuel lines from fuel pump (FP) or ejector units.

- Use a small tool when disconnecting fuel line connectors.





Lift connector as illustrated. At the same time pull the fuel line and lift it away from the unit pipe sleeve.

- Wiring for each unit.

AA7

Lift out unit





Remove:

- Collar, use tool 999 5485-1.

- Fuel pump (FP) unit or ejector unit.

Note!
The collar must always be reinstalled. Otherwise the tank pipe will swell and the collar will be hard to install causing leakage.

AA8

Installing unit

Install:

- A new rubber seal.

- The unit. Carefully insert it and position horizontally. There are two marks above the hole to help positioning.

- Collar. Tighten to 45 Nm (33 ft.lbs).

Use tool 999 5485-1.

Check that unit pipe sleeves are horizontal when the collar has been tightened.

Note!





If is important that the fuel lines on the unit are within +/- 1.5° of horizontal. The dotted line in the illustration.

Use the marks on the fuel tank.

If the unit is not properly installed, the position of the level sensors in the fuel tank will result in an incorrect fuel gauge reading.

AA9

Installing fuel lines

Install:

- Fuel line connectors.

The connector should click when it locks onto the pipe sleeve.

Check by pulling the connector.





- Push fuel lines into the fuel tank clips as marked on the illustration.

- See also section: AA11.

Note!
It is important to connect the expansion tank hose from the upper nipple to the roll-over valve, and the hose from the lower nipple to the fuel tank.

AA10

Securing wiring and fuel lines





Install:

- Cable from fuel pump (FP) or ejector units. Clip into clip and secure with tie straps and tape. See section: AA12.

AA11

Replacing fuel tank





Remove and transfer or replace:

- Fuel filler pipe.

- All fuel lines.

- All fuel lines must be secured in their clips. Transfer one fuel line at a time.

Adjust fuel lines carefully to minimize stresses so that they do not come loose or pop out of their clips.

- All heat deflectors. Transfer heat detectors to the new fuel tank.

Transfer pump or ejector unit as above, see section AA8.

Note
All fuel line positioning and installing must be carried out correctly. Otherwise there is a risk that pump noise will be transferred to the door of the car and create noise in the passenger compartment.

AA12

Damaged retaining clips on fuel tank

Note!





If any of the fuel line retaining clips on the fuel tank are damaged, secure the fuel lines as illustrated. Use tie straps in a figure of eight between the fuel lines.

Position pieces of tape P/N: 3537456-0 over the fuel lines and tie straps to prevent the transfer of pump noise through the door of the car.

Ensure that the heat detectors are secured with tape.

Cut pieces of tape to size and clean the surfaces where the tape is to be applied to ensure good adhesion.

Install soundproofing on top of fuel tank.

Install splashguard to the front of the fuel tank in front of the units.

AA13

Install rear axle

Reinstall:

- Rear suspension, fuel tank according to See other manual: (Service Manual: Section 4(43,46), AWD, 850 1997-).

Note!
Check that heat detector plates are correctly positioned and secured and that the distance between the exhaust pipe and adjacent components is at least 20 mm (3/4").

Start engine for leak test:

Start the engine and check that there is no fuel leakage. Check all pump, ejector and fuel filter connections. Reinstall hatches in luggage compartment.

Install wiring in rubber grommet so that the yellow tape marking is on the inside.

Install plate with connectors.

Reinstall components in luggage compartment.