Fuel Tank: Testing and Inspection

Fuel Sender Service:

CAUTION:
- Before attempting Fuel Tank Leak Check place a dry chemical (Class B) fire extinguisher near work area.
- Before removing the fuel tank for a suspected leak, make sure fuel hoses are not leaking onto the tank. Also, make sure fuel is not leaking around fuel sender assembly gasket.

ON VEHICLE
A visual inspection of the tank, and a leak-check of the fuel tank bladder are the only checks possible on-vehicle. If fuel is leaking from the tank, replace tank and check for leaks.

1. Disconnect negative battery cable.
2. Relieve fuel system pressure.
- Refer to Fuel System / Service and Repair. Service and Repair
3. Drain fuel tank.
4. Remove filler door bezel attaching screws and bezel.
5. Lift fuel tank filler pipe housing and disconnect drain hose from nipple.
6. Remove fuel tank filler pipe housing.
7. Disconnect fuel feed hose, and cap pipe on fuel sender assembly.
8. Disconnect the EVAP hose between the fuel sender assembly and the fuel tank "TEE" fitting at the "TEE."
9. Plug hose and cap open end of "TEE" fitting.
10. Disconnect EVAP hose to canister from other side of "TEE" fitting.
11. Connect a piece of hose to the open end of "TEE" fitting, and place other end into a container of water.
12. Install fuel filler cap.
13. Apply 7 to 10 kPa (1 to 1 1/2 psi) air pressure to the fuel return pipe on the fuel sender assembly.
- Continuous air bubbles appearing in container indicate a leak in the bladder. A short burst of air bubbles is common at start.
14. Replace fuel tank if bladder is leaking.

OFF VEHICLE
"Off-Vehicle" leak check requires two sources of regulated air pressure.
This check requires a fuel sender assembly and fuel filler cap to be installed in the fuel tank.

1. Cap fuel feed pipe and EVAP on fuel sender assembly.
2. Cap one end of fuel tank "TEE" fitting.
3. Connect a piece of hose to the open end of "TEE" fitting, and place other end into a container of water.
4. Tighten fuel filler cap.
5. Apply 7 to 10 kPa (1 to 1 1/2 psi) air pressure to the fuel return pipe on the fuel sender assembly.
- Continuous air bubbles appearing from container indicate a leak in the bladder. A short burst of air bubbles is common at start. Replace fuel tank if bladder is leaking.
- If no or only a short burst of bubbles appear, continue with check.

CAUTION: Equal air pressure must be applied to the fuel return pipe on the fuel sender assembly before air pressure is applied to the vent "TEE" opening, or damage to bladder may result.

6. Release air supply, and submerge tank in water or apply soap solution to outside of tank
7. Reapply 7 to 10 kPa (1 to 1 1/2 psi) air pressure to the fuel return pipe on the fuel sender assembly. With a second air source, apply 7 to 10 kPa (1 to 1 1/2 psi) air pressure to the hose connected to the "TEE" fitting.
- Air bubbles indicate a leak in the metal tank. Replace fuel tank if it is leaking.

CAUTION: Air pressure must be released from the hose connected to the "TEE" fitting before releasing pressure from the fuel return pipe on the fuel sender assembly, or damage to bladder may result.

8. Release air pressure from hose connected to "TEE" fitting.
9. Release air pressure from fuel return pipe on the fuel sender assembly.