Timing Belt Replacement

To access the timing belt, first remove the front bumper and the complete crossmember with headlights and radiator.
Next, remove the timing belt cover and unscrew the fastening pins of the cooling fan to remove it.
Loosen the tensioner (plastic pulley) of the auxiliary belt (by rotating it while leveraging the central pin with a 17 mm wrench) and slide the belt off, trying to remember the various routing around the pulleys. Then remove the crankshaft pulley (the large one with grooves located at the bottom, in front of the plastic cover); then remove the cover itself and the valve cover.
Before removing the timing belt, manually rotate the crankshaft until reaching the timing marks (camshaft mark, flywheel mark, pulley pin alignment): once aligned, mark the position of the crankshaft with a marker. At this point, remove the timing belt tensioner (plastic pulley) and take off the timing belt. Install the new tensioner by correctly inserting the tab of the rear bracket into its designated slot; position the new belt, ensuring not to rotate the pulleys and making it adhere properly. Finally, tension the belt by preloading the tensioner spring with pliers and tightening the securing pin.
Before starting the engine, manually rotate the crankshaft 2 full turns (the thermodynamic cycle of the 4-stroke engine completes in 2 rotations of the crankshaft), rechecking the timing marks: if they align, start the engine to verify its proper operation and reassemble everything (it is recommended to also replace the tensioner and auxiliary belt).
This repair should only be performed if you have good mechanical knowledge, as a simple mistake could seriously damage the engine.