How to Repair a Vehicle's Plastic Fuel Tank
- 1). Park your vehicle on a flat, hard surface.
- 2). Raise your vehicle. Place a jack underneath the vehicle and raise it to a height which allows access to the fuel tank. Lower the vehicle onto jack stands under the frame. Locate the leak and mark the area with masking tape and a pen.
- 3). Loosen the fuel tank retaining straps, with a wrench, and lower the fuel tank to the ground. Remove all wires and fuel lines from the fuel tank, labeling them with masking tape and a pen to aid in reassembly.
- 4). Empty the fuel tank into a suitable container and wipe the tank with a clean rag.
- 5). Flush the tank with soapy water for several minutes by inserting a water hose into the tank's opening, squirting in a generous amount of dish-washing liquid and flushing to remove all traces of fuel and fuel vapors.
- 6). Weld the leak. By running the hot soldering iron down both sides of the leak, a trench will be created. Using plastic from a milk jug or spray can cap, melt strips of plastic into the trench and smooth it down with the soldering iron. Allow the fuel tank's interior to air-dry.
- 7). Replace the fuel tank by reversing the steps in the removal process. Pour fuel back into the tank and check for leaks. Once satisfied with the repair, raise the vehicle off the stands and lower it to the ground.
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