'99 XK8 Convertible 4.0, I need to replace the serpentine belt and am looking for a diagram, which is the tensioner pulley?....any tips?

 

Welcome to the forum - this is a great place to pick up maintenance and repair tips from guys that really know whats going on with the XK8.

Spend a minute to look over the FAQ sections of the Forum and the sections with documents posted that you can download. In there you will find a document called the JTIS, which is the best starting point for information regarding your car. You can download the document and look up sections applicable to your specific model year - yes they are different each year.

The routing path for the serpentine belt is shown in the JTIS. (I printed an example and keep it taped under the hood.)

The tensioner is the spring loaded device which keeps an appropriate level of tension on the serpentine belt. The device includes a cast metal spring loaded tensioner (silver) and a black pulley which simply rides against the belt and applies the tension. There will be a diagram in the JTIS showing this set up but you can tell which item it is because it is not connected to anything else like the powersteering pump or alternator.

On that combination tensioner/pulley device is a hole that will fit a 3/8 socket head. You can use this to rotate the tensioner and release the pressure on the serpentine belt and simply slip it off. Thread the new one on and reverse the process to reseat the belt on the tensioner.

This is a great DIY project. If yo have problems, just ask for help.

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