Removed the t-stat housing yesterday to install a high flow t-stat. Inside the intake under the housing appeared to be a small amount of barnacles multiplying on the intake walls. Assume this is eletrolosis disintigrating the aluminum intake because of the dissimilar metals especially because of the chrome t-stat housing and iron block. I've heard a zinc anode installled in the radiator petcock hole will eliminate this action??? Anyone experienced this with their engines?:confused:

Typical arguement between aluminium and iron/steel. There are several products on the market you can add to your coolant that will cut down on this as well as an anode attached to a radiator cap. The anode is sacrificial and will disintegrate over time leaving the aluminium alone. Adding something like a water wetter or such can also help.

Good quality Anti freeze also has anti corrosion agents....
This should be changed once a yr when doing raditor cooling system maintaince, same as one changes oil/ filters on a regular basis

GM makes some good anti corrosion pellets , crush two or three and drop in radiator. Large brown pellets.