Question RE Chevy 350 ZZ4 aluminum heads

[seadog]

I have a ZZ4 crate engine that has been in my Deuce for about six years now.  

I'm ashamed to admit that I didn't pay much attention to what the spec sheet said about maintaining the cooling system so as to prevent corrosion of the heads.  I've heard everything from, "you need to use distilled water in the radiator to "no special treatment is needed."

Right now I'm just running straight antifreeze and it's time to drain and flush the system so I'm wondering what additional things I need to do to help the aluminum heads live a long time.  

...and have I potentially done any damage by letting this go this long?  

Thanks

[kb426]

My exp. has been that if you used an antifreeze that was compatible with alum. you won't have a problem. There are many variables so I don't have much of an answer for you. Unless you have driven many miles, I'd be surprised if there was any residual effects.

[rumrumm]

A lot of people suggest adding a magnesium or zinc sacrificial anode to the radiator just to be on the safe side. I have done that as I also run aluminum heads and water pump on my sbc engine. It is cheap insurance. I use one suspended from the radiator cap but there are others that screw into the bottom of the radiator. They work with metal radiators but not plastic ones.

[purplepickup]

You can test to see if you have stray voltage in your cooling system with a multimeter. This will tell you if you have a potential for electrolysis erosion.   Fix the negative lead to a good ground and put the positive lead into the coolant without touching any metal with the lead.  If the reading is more than .10V, check for good grounds from the frame to drivetrain.  Here's an article on it. http://www.carolinarodshop.com/Store/Griffin/radiator_electrolysis.htm

[seadog]

Thanks for the responses.