These models feature two types of drivebelt systems,For the models produced from 2003 to 2007, there are two drivebelts with adjusters, while later models, starting from 2008, use a serpentine drivebelt with an automatic tensioner. Since it is a material that is under great pressure and is in constant use, drivebelts become worn out and stretched, and for this reason, must be inspected regularly. Pump belt earlier models the 2007 models have used the power steering pump belt together with the alternator/AC compressor belt while the later models from 2008 have adopted the SD belt for all the accessories. To inspect the drivebelts, one has to follow the following procedure; Engine off, Hood up and use a Flashlight; with this, you check for such things as separation, cracks, fraying and so on. If any problems are visible, the belt must be replaced It is necessary to check both sides of the belt. For tension checks on S2000 for models prior to 2008 push on the belt to deflection and for models 2008 and earlier, check the drivebelt indicator for stretch. To set the belt tension for the years 2003-2007 one has to lift the car, remove the engine splash shields, and adjust the Idler Pulley or the power steering pump belt depending on the model. Said changes of belts should not be done without removal of additional parts, and when reinstalling belts, then the latter should be marked in order to be refitted properly. Once you have put in a new ribbed drivebelt, ensure it fits well in the grooves of the pulley and correct the position if it does not. For the replacement of tensioner, it is necessary to first eliminate the drivebelt, and next the bolts that mount the tensioner, and finally replace the bolts also and tighten properly.
Posted by NissanPartsDeal Specialist 
