Honda Civic Service Manual: Fuel Tank Removal and Installation (R18A9)

1.

Raise the vehicle on a lift, and make sure it is securely supported.

This procedure should be done outside in a well-ventilated area or in a properly equipped CNG shop.

This procedure will allow you to safely work on any part of the fuel system downstream of the fuel tank such as the fuel joint block or the manual shut-off valve.

NOTE: Make sure the manual shut-off valve is open.

1.

Remove the rear seat.

2.

Remove the seat back.

3.

Disconnect the connector (A) (this prevents the tank from supplying fuel to the system).

4.

Start the engine, and let it idle.

5.

After a few minutes, the engine will stall.

6.

Turn the ignition switch to LOCK (0).

1.

Remove the rear floor undercover (A).

1.

Remove the three fuel pipes (A) at the fuel joint block (B) and the two fuel joint block mounting bolts (C).

NOTE: Always use two wrenches when removing fuel pipe nuts.

1.

Lower the vehicle on the lift.

1.

Remove the left rear door assembly (A).

2.

Disconnect the connector (A).

1.

Remove the bolt (A) securing the rear seat cushion (B).

2.

While pushing down the rear seat cushion (A), pull the seat hook handles (B) to release the hooks (C).

3.

Remove the rear seat cushion.

1.

Remove the center seat belt buckle bolt (A) at the floor.

1.

Release the center seat belt (A) from the center belt guide (B).

2.

Remove the bolts (A).

3.

Remove the rear seat-back (A).

1.

Pull out the C-pillar trim (A) to release the clips.

2.

Remove the C-pillar trim.

NOTE: The front clip (B) will stay in the body.

3.

The left side is shown; repeat on the right side.

4.

Remove the front clip (A).

5.

The left side is shown; repeat on the right side.

1.

From the trunk compartment, disconnect the connector (A).

2.

From the trunk compartment, detach the clips (A).

1.

Remove the trunk floor cover (A).

1.

Remove the trunk front trim panel (A) and the trunk partition (B) as an assembly.

1.

Remove the fuel tank protector (A).

1.

Remove the gussets (A).

1.

Disconnect the speaker connectors, and remove the rear parcel cover (A).

1.

Remove the rear shelf gussets (A) in the trunk.

1.

Remove the rear floor upper crossmember gusset (A).

1.

Remove the bolts (A).

2.

Disconnect the vent hose (A).

3.

Remove the tank frame mounting bolts (A).

4.

Push the front seats forward, then cover the seats and the floor with a tarp or similar material.

5.

With the help of two other technicians, lift the frame, and slide the entire fuel tank assembly (A) into the passenger compartment. Be careful not to damage the fuel joint block.

6.

Rotate the fuel tank so the fuel joint block and the frame can clear the left rear door opening, then carefully remove the fuel tank assembly from the vehicle.

1.

With the help of two other technicians, lift the frame, and slide the entire fuel tank assembly (A) into the passenger compartment from outside the vehicle. Be careful not to damage the fuel joint block.

2.

Carefully set the fuel tank assembly to the proper position.

3.

Install the tank frame mounting bolts (A).

4.

Connect the vent hose (A).

5.

Install the bolts (A).

1.

Install the rear floor upper crossmember gusset (A).

NOTE:

1.

Remove the rear shelf gussets (A) in the trunk.

1.

Install the rear parcel cover (A), and reconnect the speaker connectors.

1.

Install the gussets (A).

1.

Install the fuel tank protector (A).

1.

Install the trunk front trim panel (A) and the trunk partition (B) as an assembly.

1.

Install the trunk floor cover (A).

2.

Install the clips (A).

3.

From the trunk compartment, connect the connector (A).

1.

Install the new front clip (A) to the C-pillar trim (B).

2.

Install the C-pillar trim (A).

NOTE:

3.

The left side is shown; repeat on the right side.

1.

Install the rear seat-back (A).

2.

Install the bolts (A).

3.

Install the center seat belt (A) to the center belt guide (B).

1.

Install the center seat belt buckle bolt (A).

1.

Install the hooks (A) to the rear seat cushion clips (B).

2.

Install the bolt (A) securing the rear seat cushion (B).

1.

Connect the connector (A).

2.

Install the left rear door assembly (A).

NOTE: Check for a flush fit with the body, then check for equal gaps between the front and rear doors, and between the doors, and the body. Check that the door and body edges are parallel.

1.

Place the vehicle on a firm, level surface when adjusting the doors.

2.

Adjust at the hinges:

3.

If necessary, replace the door mounting bolts with the adjusting bolts made specifically for door adjustment, then adjust at the door: Loosen the door mounting bolts (B) slightly, and move the door up or down as necessary to equalize the gaps, and move it in or out until it's flush with the body.

NOTE: Refer to the Parts Catalog if you need use an adjusting bolt.

4.

Check that the door and body edges are parallel. If necessary, adjust the door cushions (A) to make the rear of the doors flush with the body.

5.

Apply touch-up paint to the hinge mounting bolts, and around the hinges.

1.

Install two fuel joint block mounting bolts (A).

2.

Install the three fuel pipes (B) at the fuel joint block (C).

NOTE: Always use two wrenches when installing fuel pipe nuts.

1.

Install the rear floor undercover (A).

If a tank is empty, has less than 690±340 kPa (7.0±3.5 kgf/cm2, 100±50 psi) of internal pressure and is at an ambient temperature of 32 °F (0 °C) or less, follow the procedure below. Otherwise, fill the tank normally.

1.

Fill the fuel tank to 4,800±340 kPa (49.2±3.5 kgf/cm2, 700±50 psi) slowly (from a compressor, not from a cascade storage system).

2.

Wait 1 hour.

3.

Fill the rest of the tank normally.

1.

Open the manual shut-off valve (A).

Check for a gas leak if there is an odor coming from the vehicle. Compressed natural gas (CNG) can only be smelled, not seen.

1.

Open the hood and the fuel fill door.

2.

Connect a vacuum pump/gauge, 0－30 inHg, to the hose (A) from fuel pressure regulator P1, and apply 67.7 kPa (20.0 inHg, 508 mmHg) of vacuum.

3.

If fuel pressure regulator P2 does not hold vacuum, replace it before continuing to the next step.

4.

Inspect the fuel lines and hoses under the hood for kinks, abrasion, and other signs of damage.

5.

With the manual shut-off valve open, turn the ignition switch to ON (II), but do not start the engine.

6.

After the fuel pressure regulator shut-off solenoid valve/fuel tank internal solenoid valve operates for about 2 seconds, the fuel pressure in the fuel lines rises.

7.

Turn the ignition switch to LOCK (0).

8.

Repeat this two or three times.

9.

Within 1 minute, check for any damaged lines with a leak detector (A) (Snap-on Combustible Gas Leak Detector or Snoop Liquid Leak Detector (B)).

10.

If no damage was noticed during the inspection, turn the ignition switch to ON (II) for 2 seconds, then turn the ignition switch to LOCK (0).

11.

Within 1 minute, check for a leak at the vent hose outlet inside the fuel pipe protector (A).

12.

If you detect a leak, remove the vent hose, and check the fuel lines and fittings at the in-tank solenoid valve and the join block with a leak detector.

13.

If you cannot find the leak, raise the vehicle on a lift, remove the under-floor cover.

14.

Inspect all the fuel lines under the vehicle, visually, and with a leak detector.

15.

If you still cannot find the leak, remove the rear seat, then check all fuel lines and fittings at the fuel tank and the fuel joint block.