Removal and installation
To remove the fuel tank 8 (see fig. 30) drain the gasoline, remove the shield, remove the filler cap 6 and disconnect the wires. Disconnect the fuel supply and fuel tank ventilation pipes, unscrew the clamp bolt 10 and remove the tank. Install the fuel tank in the reverse order.
On 2102 and 21021 cars, to remove the fuel tank, you need to lift the car on a lift or place it over an inspection pit. Drain the gasoline from the tank. Having lifted the trunk mat, remove the hatch cover, disconnect the wires and hose from the fuel level indicator sensor. Remove the mudguard of the fuel tank pipe, disconnect the hose from the pipe, unscrew the nuts securing the tank to the body, lower it and disconnect the tank ventilation hose from it.
Installing the tank is in reverse order.
Cleaning and control
Carefully inspect the fuel tank along the joint line to ensure there are no leaks. If necessary, solder the leak with soft solder. Only a well-washed tank that does not contain gasoline vapors can be soldered. The tank is washed with a stream of gasoline under pressure to remove deposits and dirt, followed by; shaking. Then drain the gasoline and blow through with compressed air. These operations are repeated 2-3 times.
(The article is taken from an online resource www.VAZbook.ru)
To remove vapors and gasoline residues, the tank is filled with a 3% aqueous solution of Olinol-1 (necessarily completely), after which the solution is drained.