Water Pump Maintenance

[dilbert]

Is the impeller the main part that wears out on water pumps? It looks like for preventative maintenance I have three choices a complete water pump ($76), an impeller kit ($25), or just the impeller ($11). I'm leaning towards the impeller kit since it seems to contain all the parts that wear over time. I really want to keep this motor running as long as possible.

How often should I be doing maintenance on the water pump?
What all should I replace?
Anything else I should do while I have the lower off?

[jmay]

Unless the engine is really old or in salt water all the time the impellar is the only thing that needs to be changed. The rubber "arms" of the implellar are subject to dry rot and fail with no warning. Most owners manuals say change it every year, but that is a little over kill

[dilbert]

That's what I figured. I replaced the entire waterpump about 3 or 4 years ago and have never been in salt since then. NAPA has an impeller kit that has the impeller, O-ring seal for the housing, and metal plate for $15. I think that's what I'll get.

[jmay]

The price is spot on, its likely a Serria brand which makes most aftermarket parts with good quality for about 1/2 the price of the OEM list.