Before removing a
Timing Belt, it is recommended to mark its teeth in relation to their engagement with each sprocket and the direction in which it is fitted, as moving its position can lead to increased wear and extra noise due to run-in. If the belt has covered 30,000 miles (48,000 km) or more at the time of overhaul, it should be discarded and replaced with a new one. Immediate renewal is necessary if the belt is frayed, hard, cracked, or has worn or missing teeth, regardless of mileage. Although the timing belt sprocket teeth rarely wear, it is important to check the roller on the tensioner; if it is grooved or does not spin freely, it must be renewed. These considerations also apply to the silent shaft belt and tensioner on 1,597 cc engines equipped with them.