Toothed belt (VW Golf 3)

The camshaft is driven by a toothed belt from the crankshaft. This toothed belt with steel wire inserts is of great importance for a diesel engine. The small combustion chamber of the engine does not allow one of the valves to open and therefore open the combustion chamber slightly at the moment when the corresponding piston moves up to the top dead center. This can happen when the toothed belt breaks or (due to weak tension or the presence of a foreign object) several teeth on the pulley slip. In this case, the valve immediately hits the bottom of the piston, which leads to a dangerous so-called "piston/valve salad". The damage will be so significant that repair is impossible.

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