aluminium radiator- sacrificial anode

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gingerbreadman1977

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i have an aluminium radiator and have been told they suffer from electrolysis. apparently any more than half a volt running through the cooling system will cause corrossion. i installed a sacrificial anode in the hole where the drain plug would normally go.they sell these at summit. does anyone have any knowledge on how well a zink anode like this works? this radiator is too expensive to have it wasted with corrosion.
 
If you installed the anode, just use distilled water and 50% antifreeze. The new generation Dexcools seem to be okay and work well with alum.
 
i tested my car and it had half to 1 volt in the coolant. i was worried about it cause thats over the recommended level. so i go test my mates brand new toyoto. 4 weekes old never been touched and it has 1.5 volts. so i test another new car. what do you know 1 volt.so i come to the conclusion most cars must have a reading and alloy radiator manufacturers use this to there advantage to get out of claims . so i installed the sacrificial annode from summit. u can see it in the picture.i tried to only put thread tape on the last few threads so i get a good metal on metal contact on the first five or so threads that go in hopefully. and ill also be using distilled water . i already use GM coolant so i cant really do much more than that.ill see how it goes.thanks for everyones info. its all very good.

IMG_0997.jpg
 
wouldn't you have to have a direct connection between the metals to have it destruct?? draw current?? just because you have a voltage there don't mean shit in my opinion.....corrosiion would be faster with grounding the radiator.....

and IMO, when using good old ethelglycol antifreeze in any car for some decades now, I hever seen any corrosion problems in heads, intakes, radiators, or aluminum tstat caps.....only when using just water or some such....

I would also suggest that all that aluminum tied to the iron block would corrode much faster than anything else, but the properties of green antifreeze are such it's not a problem....

helps to change that crap every two years or so also....
 
mrvette said:
wouldn't you have to have a direct connection between the metals to have it destruct?? draw current?? just because you have a voltage there don't mean shit in my opinion.....corrosiion would be faster with grounding the radiator.....



and IMO, when using good old ethelglycol antifreeze in any car for some decades now, I hever seen any corrosion problems in heads, intakes, radiators, or aluminum tstat caps.....only when using just water or some such....



I would also suggest that all that aluminum tied to the iron block would corrode much faster than anything else, but the properties of green antifreeze are such it's not a problem....

helps to change that crap every two years or so also....
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NO YOU DONT NEED A DIRECT METAL TO METAL CONNECTION CURRENT WILL TRAVEL IN WATER/COOLANT. IT DONT MEAN SHIT? WELL IT DOES< IT MEANS THAT VOLTAGE ARCS OUT AT THE WEAKEST POINT. NORMALLY A RADIATOR TUBE.MOST COOLING SYSTEMS WILL RUN HOT WITH PURE ETHYLGLYCOL. IF U CAN GET AWAY WITH IT THAN GREAT.BUT 50/50 MIX IS WHAT IS NORMAL
 
mrvette said:
wouldn't you have to have a direct connection between the metals to have it destruct?? draw current?? just because you have a voltage there don't mean shit in my opinion.....corrosiion would be faster with grounding the radiator.....

and IMO, when using good old ethelglycol antifreeze in any car for some decades now, I hever seen any corrosion problems in heads, intakes, radiators, or aluminum tstat caps.....only when using just water or some such....

I would also suggest that all that aluminum tied to the iron block would corrode much faster than anything else, but the properties of green antifreeze are such it's not a problem....

helps to change that crap every two years or so also....
Click to expand...

Nope, I've seen it with my own two eyes.

When I got back from the Navy I got my Nova ready to fire for the first time in over three years, the 50/50 mix had corroded out the steel freeze plugs AND the head gasket on the even side of the block, as soon as I hit the key and the compression hit the coolant system the rusted out freeze plugs popped.

As for the electrolysis in the radiator, it happens, I don't know how, or why, but I've learned from the mistakes of others that when I finally get one (and electric fans) there will be a couple of ground wires and a sacrificial anode.:thumbs:

THERE IS NO REASON TO USE ALL CAPS, IT MAKES YOU LOOK LIKE A DOUCHE!
 
about the caps i only did that to seperate what i wrote from mr vettes comment, i didnt realise it seperated it automatically with a border when i quoted so sorry about that mr vette and douche smokey.
 
All I got to go on is my experiences...Dad bought mom a '63 Olds F85 4dr and the thing sat in the garage for some 25 years after it got about 36000 miles on it.....in about '87 or so, the car was finally started after I rebuilt the brake system, from m/cyl on down.....engine was fine, figger a 50-50 mix of good old e glycol and water, which was pretty much industry standard since Henry started making thise POSs....and so that aluminum 215 cu in V8 and that copper radiator were fine, had steel liners in the cylinders, I know that, took a bit to o'haul the carb...parts scarce as hens teeth....had to pull a favor from a parts guy I knew for centuries....

I also note the factory don't give a damn if the rad is grounded or not....no ground wires on a stock vette rad I have ever seen, much less Mopar is tied to the chassis with fixed mounts in my Dodge 3/4 ton Van...copper....it's an '85 with a rad bought about that time from another Mopar 440 vechicle....does just FINE on that 318....eh??

so there is a voltage potential cause of dissimilar metals...battery....there, but shorting out that potential causes more corrosion and more activity off ONE of the metals than the other....I have had freeze plug problems in the van, but really now....'85??? glycol and water...
you get more chemical activity outta a battery by completing a circuit than you do by open circuit....but in the case of the Van....it seems to not much care either way....copper steel/iron....

then there is the Olds....copper, aluminum engine/steel liners, and of course steel everywhere else....go figger....

so my experiences are that it's a NON ISSUE....glycol and water....

CASE CLOSED.......


:trumpet::devil:
 
the voltage is not from different metals or a battery etc. its from a bad earth. can be anything - starter, wipers, electric window winders . it only takes one bad earth to create the problem. finding the problem/bad earth is not that easy.normal tap water has metal in it and carries the current .whats with the case closed ?
 
SmokeyVette said:
As for the electrolysis in the radiator, it happens, I don't know how, or why, but I've learned from the mistakes of others that when I finally get one (and electric fans) there will be a couple of ground wires and a sacrificial anode.:thumbs:
Click to expand...

ANY time you have two dissimilar metals in contact with an electrolyte, you get a primary battery. The transfer of metal from the anode to the cathode corrodes the anode. We call this electrolytic corrosion.
Try this at home. Take a brass screw and a SS screw. Tie a wire to each, and immerse in salt water without them touching. You will read 1.5 volts between the bolts. Primary/ Dry cell batteries are just that.
 
big2bird said:
gingerbreadman1977 said:
the voltage is not from different metals or a battery etc. its from a bad earth.
Click to expand...

I dissagree. Example. If Smokey had removed the battery from his Nova while in the Navy, the same damage would have occured. No doubt in my mind.
Click to expand...


Bird has to appreciate this...my story of a UNGROUNDED NUCLEAR POWER PLANT.....

at any rate, when the plant head engineer called a year later to tell me WTF was the matter with our gear, that sensed the UNGROUNDED condition...

and told me that plant was in FACT not grounded....fucking NUCLEAR POWER plant.....

lets just say is was:shocking::shocking::shocking:

funny, but true.....so lets not say nuttin about 'bad earth'...ok???

serious as heart attack....:drink::beer:
 
on tom dewitts site there is a section on electrolysis and what causes it. have a read if your interested..it goes on and on about 2 main points....a bad ground and distilled water.
 
big2bird said:
gingerbreadman1977 said:
the voltage is not from different metals or a battery etc. its from a bad earth.
Click to expand...

I dissagree. Example. If Smokey had removed the battery from his Nova while in the Navy, the same damage would have occured. No doubt in my mind.
Click to expand...

There was no battery on the Nova while it was "in mothballs" the battery was removed and put on my Honda that I had at the time.

1200 cranking amps on a Honda is just a little overkill.
 
gingerbreadman1977 said:
on tom dewitts site there is a section on electrolysis and what causes it. have a read if your interested..it goes on and on about 2 main points....a bad ground and distilled water.
Click to expand...

I read it.
1)The use of distilled water is to minimise calcium carbide. This mineral (salt) corrodes aluminum by itself.
2)His descripsion of electrolysis is actually about external currents. This is electroplating, a different animal, but with similar results.

"Electrolysis is two dissimilar metals in contact with an electrolyte." This is an age old problem with any plumbing. Your water heater has a sacraficial anode. When it's gone, your water heater corrodes rapidly.
And it does it without any headlights present.:D
 
SmokeyVette said:
There was no battery on the Nova while it was "in mothballs" the battery was removed and put on my Honda that I had at the time.
Click to expand...

In this case, without occasional circulation of the water pump, the coolant layered out, and the exposed cast iron corroded, flaked off, and settled in direct contact with the back side of the freeze plugs, accelerating the corrosion.
When "mothballing" , I always recommend pure coolant, or draining the system completely.
 
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