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Old 08-25-2020, 03:12 PM   #1
tubman
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Join Date: Dec 2013
Location: Minnesota, Florida Keys
Posts: 10,259
Default Sacrificial Anode

I have always been a little concerned about corrosion of the aluminum heads that I have on a couple of engines.I thought about it, but never did anything about it because there didn't seem to be satisfactory solution. Recently, I had to put valve guide seals in my Corvette, which required pulling the heads and (aluminum) intake manifold. Quite frankly, I was surprised to see the amount of corrosion and corresponding metal loss on the manifold. I try to keep fresh antifreeze in my cars every 3 or 5 years, but I didn't like what I saw. As soon as I got the car back together, I decided it was time to do something about it.

I was looking on the internet for something, and I finally got to Amazon, and even they didn't have anything I liked. I did see however, that they had Magnesium "stink rods" for RV water heaters relatively cheap. Two 3/4" by 9 1/4" rods were $14.90 with free shipping. I ordered a couple to see what they looked like. When I got them I went to work and made the pictured device. It's just a brass washer soldered to the bottom of the radiator cap and a short length of steel chain attached to the longest chunk of the rod I could get through the radiator neck. Since the rods were magnesium, they are lower on the galvanic table, and therefore should corrode before the aluminum heads. I can make 6 sacrificial anodes out of 2 rods, and the chain, screw, and brass washer are incidentals I already had, so these came out to $2.50 each, which is quite a bit cheaper than anything out there and they have a lot more mass in the sacrificial anode.

I put one in the Corvette, too.
Attached Images
File Type: jpg IMG_1725.jpg (59.9 KB, 98 views)
File Type: jpg Galvanic Table.jpg (20.7 KB, 61 views)
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