Water pump impellor replacement - 2009 Mariner 30 HP

My dad has a question about his outboard. He can't find the manual for it.
"How do I replace the water pump impellor on a 2009 Mariner 30 HP portable two stroke outboard LW (light weight)?"
He says there is a particular order you have to follow and he doesn't know what it is.
Here is a summary of the info he has given me.
Make: Mariner
year: 2009
Horsepower: 30 HP
Model Number: 7030312UL
Made in Japan
Any help would be greatly appreciated.

If you need a manual, one can be purchased here

http://www.marineengine.com/manuals/seloc/mercury.html

Otherwise, I have no experience with this vintage engine, so perhaps someone else who does can assist.

I believe you actually have a 2006 model built by Tohatsu (not sold in North America). It could have been sold as a 2009 model, but that model makes it a 2006 build.

Unfortunately, most of us on this board are based in North America. These 2 strokes never hit out market due to emissions laws so at least on the Merc board we can be of next to no assistance.

Try posting on the Tohatsu/Nissan section - either Tohatsu_Guru (Alvin) or Pvanv (Paul) might be able to assist if they have any experience with the 2 strokes, provided the newer models available in Europe are close to what we used to have here...