[Brian in Tucson]

The previous owner of my 01 had an ongoing relationship with a garden hose. When I pulled the engine, I noticed a lot of scale in the water pump housing and other coolant connections to the engine. I'm not going to use a flush chemical, but will (as finances permit) either buy new radiators or have them boiled out at a radiator shop. The replacement engine and new water pump have no scale--the previous owner of my engine did his/her due diligence in that regard.

You have to pull coolant hoses off the front of the engine anyway, it's a good time to evaluate the hard water deposits.