Are you sure you need a water pump? Jim is correct in saying the fan is not attached to the pump. If the fan came off it sounds like you have a problem with the fan-clutch assembly or the pulley assembly it is mounted to.

The water pump is on the drivers side of the engine underneath the intake manifold, and it is not a fun job to replace. If it is bad, be sure to have plenty of socket extensions, swivel attachments, and foul language prepared before you start.

Good Luck!!

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