I just got my new seawater pump for my 496. This is the expensive brass one. It has the impeller in it and ready to go but it did not come with a new pulley. It appears that the pulley unthreads from the shaft and can be put onto the new pump shaft. It looks straight forward but my shop manual says that special tools are required. Has any one else thats replaced this pump had to swap pulleys and are there special tools required?

That pulley is pressed on. You will need to take the rear cover off and support the shaft as you press the pulley on the shaft. Then re-install the impeller and cover. What ever you do, do not press the pulley on while not supporting the shaft, you can ruin the bearings and seals and maybe the housing.

John S.