ARCHIVE Wits' End- I really hate galvanic corrosion

[NLXTACY]

Ever heard of galvanic corrosion? Well after seeing what kind of damage it can do inside of our engines, I decided I really needed to do something about it.

Here is the start of what will be a solution for all 80 series owners and right after, 100 owners. Corrosion is a huge issue especially if you have an aluminum radiator.

One way to remedy it is to use a sacrificial anode. In this case zinc because it’s a less noble metal. With the coolant flowing (the electrolyte) ions will always try to pull electrons from weaker dissimilar metals. In our case, aluminum. Well introducing zinc makes the ions favor corroding the zinc instead of aluminum.

Right now this piece is ready but I still need to ground it for those with plastic tanks. Almost there.

Feedback welcome. I feel like I'm missing something but I'm not sure what it is

 

[nickolai]

So it replaces the drain cock? That's cool.

 

[BlueCruiser84]

That’s awesome.

 

[jpoole]

Years spent in the saltwater sailing world certainly taught me to respect the power of galvanic corrosion. With the 80 and our other cars I have just taken to keeping the coolant fresh and non-conductive but I'm glad to add a belt with those suspenders.

Seems like there are zinc and magnesium anodes available for auto cooling systems in a variety of forms including radiator caps. I haven't looked into how they are wiring them up or observed/reported benefits. I look forward to seeing how much decay your Zinc anodes see after a year or two in place.

Thanks for bringing this and so many other solutions to market for us 80 owners!

 

[unclegit]

That's damn genius.

When can has ?

 

[NLXTACY]

Years spent in the saltwater sailing world certainly taught me to respect the power of galvanic corrosion. With the 80 and our other cars I have just taken to keeping the coolant fresh and non-conductive but I'm glad to add a belt with those suspenders.

Seems like there are zinc and magnesium anodes available for auto cooling systems in a variety of forms including radiator caps. I haven't looked into how they are wiring them up or observed/reported benefits. I look forward to seeing how much decay your Zinc anodes see after a year or two in place.

Thanks for bringing this and so many other solutions to market for us 80 owners!

it’s been used in cars for decades. It’s definitely not an idea unique to me. All I’m doing it making it pretty and bespoke to our trucks.

 

[NLXTACY]

That's damn genius.

When can has ?

just figuring out if I’m missing something stupid before I go into production.

 

[BILT4ME]

Please explain why I need this, when I didn't know I needed it.

 

[NLXTACY]

Please explain why I need this, when I didn't know I needed it.

keep dissimilar metals isolated, keep up with your coolant changes and only ever use distilled water and you never need it.

 

[jpoole]

@NLXTACY please correct me if I'm wrong on this but to answer @BILT4ME my take on this is that if the coolant in your 80s cooling system is ever conductive that the more noble metals will eat the less noble ones. Of note, the aluminum bits connected to our coolant systems like the rad. and the cyl. head will start to erode. This is why you use non-conductive distilled water and coolant solutions that include corrosion inhibitors vs. straight tapwater which is conductive in most parts of the world and will lead to metal erosion, boiler scale, etc... I assume that this zinc anode will be bonded/wired to the head and/or rad. directly or indirectly so that the zinc erodes instead of the aluminum. There are other aluminum bits in the coolant system as well as I recall like the elbow/plumbing over the t-stat, etc. Most of that is electrically bonded to the block already so the only outliers from the block may be the rad. and header cores? This is where @NLXTACY get's to work his magic and figure out how/if to try to protect those, etc. or to test and figure out how this works without extensive bonding etc. I'm guessing there's documentation on this out there as well and perhaps bonding isn't even needed?

Installing one of these falls into the easy/good insurance that saves you if you wait too long to change coolant or similar.

Here's a chart that shows who eats who:

 

[NLXTACY]

You’ve got it

 

[Desert Dino]

Let's do an experiment?

Let's take 2 plates the same size unpainted untreated, 1 from carbon steel and 1 from Aluminum (Al)

Let's put them outside in the garden, exposed to elements why do you think the iron will rust and corrode where as the AL not at all. Al hould corrode more than Iron, Al is less noble metal

Why no one installs sacrifice anode on AL boats and ships ?

Disclaimer - I have a PhD in Chemistry and was the Chief Chemist of a large shipping organization

 

[NLXTACY]

Let's do an experiment?

Let's take 2 plates the same size unpainted untreated, 1 from carbon steel and 1 from Aluminum (Al)

Let's put them outside in the garden, exposed to elements why do you think the iron will rust and corrode where as the AL not at all. Al hould corrode more than Iron, Al is less noble metal

Why no one installs sacrifice anode on AL boats and ships ?

Disclaimer - I have a PhD in Chemistry and was the Chief Chemist of a large shipping organization

now connect them together with no isolator in the garden with a stream passing over them

 

[NLXTACY]

@Desert Dino i should have PM’d you first when I was considering making this

 

[WarDamnEagle]

Let's do an experiment?

Let's take 2 plates the same size unpainted untreated, 1 from carbon steel and 1 from Aluminum (Al)

Let's put them outside in the garden, exposed to elements why do you think the iron will rust and corrode where as the AL not at all. Al hould corrode more than Iron, Al is less noble metal

Why no one installs sacrifice anode on AL boats and ships ?

Disclaimer - I have a PhD in Chemistry and was the Chief Chemist of a large shipping organization

I'll play. Aluminum corrosion takes the form of aluminum oxide which is an extremely hard compound which actually protects the surface of the aluminum from any further corrosion. If you are adding this anode to save your aluminum radiator then I think it's pretty much unnecessary. Not saying it might not be helpful in other areas like the block, etc. but I haven't thought any further than the aluminum material. Of course I've been wrong before.

 

[NLXTACY]

I'll play. Aluminum corrosion takes the form of aluminum oxide which is an extremely hard compound which actually protects the surface of the aluminum from any further corrosion. If you are adding this anode to save your aluminum radiator then I think it's pretty much unnecessary. Not saying it might not be helpful in other areas like the block, etc. but I haven't thought any further than the aluminum material. Of course I've been wrong before.

no, actually I wasn’t worried about my radiator because I anodized it

but thermostat housing, coolant outlet, etc

 

[WarDamnEagle]

no, actually I wasn’t worried about my radiator because I anodized it

but thermostat housing, coolant outlet, etc

I don't know what those materials are made out of. If they are aluminum then I stand by my comment.

 

[NLXTACY]

I don't know what those materials are made out of. If they are aluminum then I stand by my comment.

aluminum. I take care of my stuff properly so I’ve never had to deal with it. But I’ve worked on, and working on, enough of these to have seen plenty of corroded pieces. Thermostat housings, water pump sometimes, timing covers. Heads not usually. Heater cores yup and radiators for sure.

 

[WarDamnEagle]

I'm not knocking the concept but I'm not sure aluminum is the correct material for a sacrificial anode that isn't electrically bonded within the aluminum to the material that it's protecting. I think your anode is going to oxidize and Al2O3 is an insulator, not a conductor. So once the anode oxidizes it will not corrode any further. Again, I've been wrong before.

Edit: Sorry; I see now that the anode is zinc.

 

[NLXTACY]

I'm not knocking the concept but I'm not sure aluminum is the correct material for a sacrificial anode that isn't electrically bonded within the aluminum to the material that it's protecting. I think your anode is going to oxidize and Al2O3 is an insulator, not a conductor. So once the anode oxidizes it will not corrode any further. Again, I've been wrong before.

Edit: Sorry; I see now that the anode is zinc.

I was gonna say...