Fan belts or drive belts are important for the proper functioning of an engine hence need to be checked regularly due to wearing out. They can be found at a left end of an engine and their number may vary depending on the accessories one has installed. These belts should be examined for signs of damage by turning them off. If any defects are noticed, a new belt should be put in place. Tightness of the belt is checked by applying pressure and watching as it bends. This is done by adjusting the belt-driven accessory on the bracket. In replacing a belt, take it off from the crankshaft pulley with possible necessity to remove another belt or engine mount bolts for clearance purposes. Replace both belts together and ensure that they fit well into groves on pulleys. Make necessary adjustments to your belt(s).