how can i replace the water pump on a toyota estima diesel?

The man my company sub most of our work to told me it isn't too bad to do.
The key thing to remember is that in order to fit your new water pump, the old one must first be removed.
Also, it is imperative to keep the engine switched off throughout the repair for health and safety reasons.

Hope this helps.

Fwaddar Motors
July 2009