Two weeks worth of PB Blaster and a pickle fork worked perfect not the proper tool but by working my way all the way around and gentle taps another rusted part saved.
A thermostat may help, in that the engine would warm up enough to vaporize the moisture in cooler weather. I use thermostats to slow down the water flow, so it does not pump out the overflow at higher speeds. The cars also run better in cold weather.
