With normal belt tension, its deflection under a force of 98N (10 kgf) should be 10-15 mm...
...between pump pulleys and alternator...
...or 12–17 mm between pump and crankshaft pulleys.
We adjust the belt tension by shifting the generator (with loose nuts of its fastening): from the engine to increase the tension or to the engine to decrease the tension.
To replace the belt, loosen the nut securing the generator to the tension bar...
... head «at 17» on a carbureted engine...
...or head «at 13» - on injection engine.
We shift the generator to the cylinder block to loosen the belt tension.
We shift the generator, acting on it with a screwdriver as a lever in the slot of the tension bar:
on a carburetor engine;
on an injection engine.
On the engine 21214 remove the crankshaft position sensor (see Removing the crankshaft position sensor).
We take off the belt.
On a carburetor engine, it has to be removed through the gap between the radiator and the casing.
Install the belt in reverse order. Turn the crankshaft clockwise two turns and check the belt tension. Excessive belt tension causes increased loads on the alternator and pump bearings.