Drivebelts are also the parts that must be inspected periodically because they can easily go out of order with time. The quantity of belts depends on the car accessories, driving parts of the automobile like the coolant pump, the power steering pump, air conditioning compressor, air injection pump in addition to the alternatives like alternator, and the air conditioning or cooling system. The viscous cooling fan and cowl can be taken off so that it can be easily reached during inspection. With the engine off, test the belts and see whether there are any cracks, separation, fraying and glazing and check both sides by bending the belt. In 4 pistol engines, (where there was only 1 drivebelt), loosen the tensioner bolt, loosen the adjuster nut and take off the ceramic blades and shroud of the cooling fan, foo-ooliantly. Attach the new belt in the order noted: weighing the tensioner pulley first, keeping it in position, and pulling it at the required tension as per the requirements of the individual model. In models where the scale is graduated, position the tensioner pointer with the correct graduation depending on the presence or absence of power steering in the vehicle. In persons who have only one thick mark, bring into coincidence the pointer and the thick line on the scale. Some 4-cylinder engines (that have multiple drivebelts) might need to have the under-shield of the engine removed in order to access it. Change alternators and power steering pump by replacing the belts in the device and settling them at right tension. In the case of air conditioning compressor belts, dismount the correct drivebelts, make the compressor adjust and attached the substitute belt with proper tension. For 6-cylinder engines, the same process is involved, starting with the removal of the cooling fan blades and shroud, then there is removal of the tensioner and fitting the new belt, making sure that it fits into position and is then tensioned within the model directions.