Fuel Tank

This procedure removes and replaces the fuel tank on a 1970 AMC Rebel Machine, including draining fuel, disconnecting lines and electrical connections, and removing tank mounting straps.

Warnings

Tools required

Parts

• Fuel tank mounting strap kit × 1 — Use OEM specification or quality aftermarket
• Fuel filler neck hose × 1 — Use OEM specification
• Fuel tank vent hose × 1 — Use OEM specification
• Fuel tank sending unit gasket × 1 — Use OEM specification
• Fuel line rubber hoses (if deteriorated) × 1 — Use fuel-rated hose
• Hose clamps (various sizes) × 6 — Stainless steel worm-drive clamps

Preparation

1. Position vehicle on level concrete surface outdoors or in a well-ventilated garage with all ignition sources extinguished
2. Place fire extinguisher within immediate reach of work area
3. Disconnect negative battery cable to eliminate all electrical ignition sources
4. Allow exhaust system to cool completely if vehicle was recently running
5. Apply wheel chocks to front wheels
6. Relieve fuel system pressure by removing fuel filler cap
7. Drain fuel tank to less than 1/4 full using approved siphon pump and transfer to approved fuel storage containers (Note: If tank must be completely drained, continue siphoning until empty)
8. Raise rear of vehicle with floor jack and support securely on jack stands positioned on frame rails
9. Verify vehicle stability before working underneath

Procedure

1. 1

   Disconnect fuel filler neck and vent
   Locate the fuel filler neck hose connection at the rear of the tank near the driver side quarter panel. Loosen the hose clamp securing the filler neck to the tank inlet pipe using a flat blade screwdriver or socket. Slide clamp back on hose. Twist and pull the filler neck hose off the tank inlet pipe. Locate the smaller vent line near the filler neck and disconnect it in the same manner. Allow any residual fuel to drain into a shop rag or container.
2. 2

   Disconnect fuel sending unit wire
   Locate the fuel gauge sending unit wire connection on top of the fuel tank. This is typically a single wire with a push-on connector. Pull the connector straight off the sending unit terminal. On some Rebel models, there may be a ground wire attached to a tank mounting bolt - note its location for reinstallation.
3. 3

   Disconnect fuel outlet line
   Locate the fuel outlet line at the front of the tank. This is a 5/16" steel line that runs forward to the fuel pump. The connection may be a compression fitting or threaded fitting. Use line wrenches if available to avoid rounding the fitting. Hold the tank fitting stationary while loosening the line nut. Once disconnected, immediately cap or plug the line and tank outlet to prevent fuel spillage and contamination. Expect residual fuel spillage - have rags ready.
4. 4

   Position support for fuel tank
   Position a transmission jack or fuel tank jack under the center of the fuel tank. Raise the jack until it just contacts the tank bottom, providing support but not lifting. If using a floor jack, place a wide piece of wood across the jack saddle to distribute load and prevent tank damage. Ensure the tank is stable on the jack before proceeding.
5. 5

   Remove rear tank mounting strap
   Locate the rear fuel tank mounting strap that wraps around the bottom of the tank. The strap ends bolt to brackets on the vehicle frame on both sides. Apply penetrating oil to the strap mounting bolts and allow to soak. Remove the bolts securing the rear strap to the frame using appropriate sockets or wrenches (typically 1/2" or 9/16"). The driver side bolt may be difficult to access. Once both bolts are removed, carefully lower and remove the rear strap.
6. 6

   Remove front tank mounting strap
   Locate the front fuel tank mounting strap. Apply penetrating oil to mounting bolts. Remove the bolts securing the front strap to the frame brackets on both sides. Once both bolts are removed, carefully lower and remove the front strap. The tank is now supported only by the jack.
7. 7

   Lower and remove fuel tank
   Carefully and slowly lower the jack while guiding the tank down. Watch for any remaining connections that may have been missed. As the tank lowers, ensure the filler neck completely separates from the tank and doesn't hang up. The tank may need to be angled or rotated slightly to clear the rear axle and frame. Once clear of the vehicle, continue lowering and slide the tank out from under the vehicle. Place tank on ground in safe location away from work area.
8. 8

   Inspect and clean mounting area
   With the tank removed, inspect the tank mounting straps for severe rust, cracks, or deformation - replace if damaged. Inspect frame mounting points for rust damage or structural weakness. Wire brush the strap mounting bolt holes and apply penetrating oil to clean threads. Inspect fuel lines, filler neck, and vent tubes for damage or severe corrosion. This is the opportunity to replace deteriorated hoses and inspect the sending unit.
9. 9

   Prepare new or cleaned tank for installation
   If installing a new tank, transfer the fuel sending unit from the old tank to the new one using a brass punch and hammer to tap the locking ring counterclockwise (do not use steel tools that can spark). Install a new sending unit gasket. If reusing the original tank, thoroughly clean the exterior and inspect for leaks, rust-through, or damage. Replace the sending unit gasket regardless. Ensure the tank inlet pipe and outlet fitting are clean and free of debris.
10. 10

    Position tank on jack and raise into place
    Place the fuel tank on the transmission jack or floor jack with wood support. Ensure it is centered and stable. Carefully raise the tank up into position under the vehicle. Align the tank so that the filler neck inlet is positioned to meet the filler hose, and the outlet fitting is accessible for the fuel line connection. You may need to angle or rotate the tank to maneuver it past the rear axle. Raise until the tank is in its final mounted position against the frame.
11. 11

    Install front mounting strap
    Position the front mounting strap (new or original if in good condition) around the front of the tank. Align the strap ends with the frame mounting brackets. Install mounting bolts finger-tight on both sides. Do not fully tighten yet - leave straps loose enough that tank position can be adjusted.
12. 12

    Install rear mounting strap and tighten all straps
    Position the rear mounting strap around the rear of the tank. Align strap ends with frame brackets and install bolts finger-tight. Verify the tank is properly positioned with all connections accessible. Tighten all four mounting strap bolts evenly in a cross pattern to ensure even pressure. Tighten securely but do not overtighten as this can damage the tank. Typical torque for these bolts is 25-30 ft-lbs, but no specification is verified for this vehicle - use judgment to achieve secure mounting without crushing straps or deforming tank.
13. 13

    Reconnect fuel outlet line
    Remove the cap or plug from the fuel outlet line and tank fitting. Align the fuel line with the tank outlet fitting and thread or press the connection together. Use line wrenches to tighten the fitting securely while holding the tank fitting stationary to prevent it from turning in the tank. Ensure connection is tight but do not overtighten and strip the fitting.
14. 14

    Reconnect sending unit wire and ground
    Press the fuel sending unit wire connector firmly onto the sending unit terminal until it clicks or seats fully. If there was a ground wire attached to a mounting strap bolt, reconnect it now ensuring good metal-to-metal contact for proper grounding of the sending unit.
15. 15

    Reconnect filler neck and vent hoses
    Slide new hose clamps onto the filler neck hose and vent hose. Push the filler neck hose fully onto the tank inlet pipe - it should slide on at least 2 inches. Position the clamp over the connection area and tighten securely. Repeat for the vent line connection. Ensure both hoses are routed without kinks and have adequate clearance from the exhaust system and suspension components.

Reassembly

1. Remove jack from under vehicle and lower vehicle to ground
2. Reconnect negative battery cable
3. Add fuel to tank (start with 2-3 gallons for initial testing)
4. Do not start engine yet - perform leak verification first

Verification

• Inspect all connection points for fuel leaks while tank is static - look for drips at outlet line, filler neck, and vent connections
• Turn ignition key to ON position (without starting engine) to activate fuel pump if electric, and observe for leaks - have fire extinguisher ready
• Check fuel gauge operation - needle should move off empty if fuel was added
• Start engine and allow to idle while carefully inspecting all connections for leaks from underneath vehicle
• With engine running, check that fuel gauge reads accurately for the amount of fuel added
• Turn off engine and perform final inspection of all connections, strap tightness, and verify no fuel odor or visible leaks
• Test drive vehicle and recheck all connections afterward for any seepage or drips
• Monitor fuel gauge operation during test drive to confirm sending unit is functioning properly

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