- 1). Drive your car, if possible, until the fuel tank is almost empty. Raise and support the front and rear of the car with jack stands under the frame. Disconnect the rubber exhaust hangers at the muffler by hand, popping them off the metal hanger nipples, allowing the muffler to hang limply. Remove the gas cap to depressurize the tank.
- 2). Loosen the clamps on the overflow and fill pipes at both ends using the screwdriver. Remove the two rubber pipes. Siphon off any remaining fuel from the tank using an electric or hand-operated fuel pump. Place the suction line into the fuel tank's overflow hose and pump the fuel out into a gas can.
- 3). Support the fuel tank loosely with the jack. Place the plywood piece between the jack pad and the tank to keep the jack from denting the tank.
- 4). Loosen the nuts on the fuel tank straps using the ratchet and socket. Remove the bolts and swing the straps down and away from the tank without bending or twisting them.
- 5). Lower the jack and fuel tank slowly until you can reach the fuel lines and electrical connections. Disconnect the fuel pump connector on the top of the tank. Start the car and allow it to run until it stalls. Crank the engine over for another three seconds to relive residual pressure in the fuel lines. Disconnect the negative battery cable to remove chances of stray sparks. Remove the fuel lines. Note which is pressure and which is return.
- 6). Rotate the locking ring on the top of the tank counterclockwise by hand and remove the fuel sending unit and pickup from the tank, making note of orientation. If the locking ring is stubborn, use a non-sparking implement such as a wooden dowel or brass punch to unlock the ring. Strike the punch or dowel lightly with a hammer to pop the ring loose.
- 7). Install the fuel sending unit and pickup in the replacement tank and rotate the locking ring clockwise by hand. Place the new tank on the jack and plywood and roll it into place under the car.
- 8). Raise the jack high enough that you can reconnect the pressure and return fuel lines. Reconnect the fuel pump electrical connector. Lift the tank fully into position.
- 9). Lift the tank straps into position, insert the strap bolts into the openings in the frame and tighten the bolts to 35 foot-pounds with a torque wrench and socket.
- 10
Replace the overflow and fill pipes between the tank and fuel filler opening and tighten the clamps with the screwdriver. - 11
Lower the car to the ground. Put at least a few gallons of fuel into the tank. Reconnect the negative battery terminal. Turn the ignition to the "On" position for 10 seconds to allow the fuel system to pressurize. Start the engine. It may take several tries before the engine runs smoothly.
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