It was not a big surprise that the fuel tank was completely rusted as it had been in the engine bay without the engine in front of it or an engine lid for that matter. One thing that did surprise me was that it was that it did not leak! To start work on the tank, remove it by first emptying the tank through the bottom fuel line and then loosening the two bolts that hold the metal straps in place that secure the tank.
Once out, remove the fuel level meter and fuel line outlet at the bottom of the tank. I then sent it away to be sandblasted and powder coated, to provide a hard wearing and heat resistant finish.
When the tank came back I set about cleaning the inside of the tank:
- Seal the fuel line outlet at the bottom of the tank;
- Fill the tank with clean little pebbles and add diesel;
- Rock the entire tank to move the pebbles around the entire tank to loosen rust from the inside of the tank;
- Leave the mix in there for a few days, and;
- Examine the sludge that comes out of the tank;
- Repeat as many times as required.
Once cleaned inside and out, I added some protective rubber strips on the tank to prevent the metal straps that secure the tank from scratching the new paint. Finally we polished the (original!) tank cap using metal polish compound and a polishing brush on a drill.