OK, Here's a question. Most radiator's are mounted in rubber cushions. Thus making them ungrounded other than the fluid that flows through them.
Now of course we don't want electrolysis eating away at out precious radiator's. And we all know we don't wish to read any voltage above maybe .3 of a volt in our coolant.
And if our engine is properly grounded. We really shouldn't see any voltage in our coolant.
But.
Should the radiator be grounded?
Thought's please.

 

I put a sacrificial electrode ( can’t think of the correct term)in the plug opening in the radiator. It will attract whatever corrosion develops . They use similar things on boats that live in salt water to keep the electrolysis from attacking propellers.

 

Zink, or zink bars...problem is I don't think Red paint will stick to it that good...
lol...

 

What ya' need to do is......naaaa....that won't work.
What about a zinc bar bent into a V-shape and pushed into the radiator outlet. It should be o.k. there and easily removable when it's crusted over.

4Vettes...lettu e khow how it works out (the original radiiator tans were so thin I could crease them with my fingernail)

 

I have a Flex-a-Lite 32060 in my radiator (Amazon Link, since they remember stuff like that).

It seems that adding a ground can't hurt, either.
https://bobistheoilguy.com/forums/th...nd-wire.69753/

EDIT: Leaving the radiator isolated is probably your best bet. (See below)

 

An anode is clearly a good thing. And I have one on order.
I have seen the Bob's the oil guy post on line. As well as numerous other articles and forum posts from all over. Some think you really should ground your radiator. Others say your providing a path for the current which will accelerate electrolysis. The more I read, the more confusing it gets. Seems it's split down the middle.
We have a resident chemistry teacher on here, what does Leigh think?
We have a electrical engineer on here, sorry forget his name, what does he think?
Seriously, this is a hottly debated topic.

 

My radiator hasn't been touched since being installed at the factory 48 years & 78k ago.
I've done regular flush & fills & that's it. Except for a stuck thermostat once, I've never had a cooling problem.

Overkill IMO...

 

Is it aluminum?

 

With my car the previous owner who had it for about 14 years never put inhibitor in the coolant because he thought he didn't need it because the car was garaged all the time, he was only thinking of the anti freeze part not the corrosion part of the additives function. The zinc die cast thermostat/radiator connection acted as a sacrificial anode so fortunately everything else was okay. Had to replace that part it was very pitted.

 

On my 98 Wrangler with LS6 swap alum radiator no ground strap or zinc anode. Its been 15 years and no issues. But I do drain and replace the anti-freeze every two years.

 

Electrolysis comes by immersing dissimilar metals in a conductive solution. I am no chemist, but I manage a small fleet of boats in my day job.

The different molecules of the metals will cause one to sacrifice ions to the other - there is your corrosion.Same principle for your lead acid car battery.

With many boats, a stainless prop will steal ions from aluminum and corrode away the aluminum. By placing a softer sacrificial anode (magnesium or zinc depending on type of water) near the other metals, the softer of the metals will get eaten.

As far as your radiator, you only have aluminum in direct contact with the coolant. As long as there is no other metals in the rad, there should be no electrolysis as we see with boats.

The “corrosion” you see is probably “scaling” from minerals in the water….

 

Here's another website that agrees with @DWAVette.

Yes: Clean coolant and a sacrificial anode.
No: Grounding the radiator.
Bonus: Australian website.

https://trade.mechanic.com.au/news/e...-demystified1/

 

Was hoping for more information. Still listening.

 

That might be all you get. Just having an aluminum radiator makes you an outlier from the "keep it stock" crowd.

You might get better answers in the C5 section, or at LS1Tech.com

 

While it is true there are a few keep it stock guys on here. I'm willing to bet the vast majority of us on the C3 forum run a aluminium rad.
As per grounding a radiator. I don't believe I ever specified which type or any type should be grounded, or not.

 

You'd be surprised. If maintained, the stock radiator could still be working just fine today. None were grounded from the factory (that I am aware of) or came with zinc anodes.

All C5s have aluminum rads. Do any of them call for grounding? Do any of them have provisions to add a ground, like a factory spade connector brazed onto the side? I don't know either, which is why I suggested looking there. Can you get 50 years out of an aluminum radiator? I don't know. But if you can get 25 years out of one without grounds, there'd be "keep it stock" C5s out there that have done it.

And if someone has an answer to any of these unknowns, please let us know!

 

I'd say un-grounded. Most modern aluminum radiators have a plastic top and bottom cap. No way to make a ground. Seems to work fine. I use .4 volts as the determining factor for antifreeze change intervals, not time. Below .4 volts it's good.
Take your meter, stick one prong in the antifreeze in the radiator, put the other prong on a good ground.

 

OK, So just when I think NO ground. I read in another thread over in the tech forum Leigh says to put a small ground wire on a Aluminium rad.
Which is correct???

 

My personal thoughts but I have no scientific data to back me up: Copper radiators as in OEM didn't have as much of an issue as the aluminum ones that a lot of us are using. I don't know why but it seems this became more of an issue as more of us switched to the aluminum ones. But the aluminum radiators on our cars do not have plastic tanks on them, just aluminum so that is a lot of dissimilar metal to our engines and again, my experiences have been that aluminum corrodes more than copper. I put the anode in to replace my drain plug and never looked back. It can't hurt, it is cheap and I won't have to touch it until I need to drain the radiator, at which time I can see for myself that it is working.

 

Ok Doc.
There are three different kinds of corrosion you can get in a car cooling system. And the incredibly thin Aluminum radiator or the heater core is the likely first failure point.

1. pH
2. Galvanic
3. Electrical

pH - One of the reasons is water is extremely effective at absorbing things. And dissolved metals are called ions. Incredibly pure water will even absorb CO2 from the air and become very slightly acidic. Coolant always needs a corrosion inhibitor because of this. They do wear out or break down. So must be replenished regularly. Every couple years is the typical thumb rule. Test for with a pH meter. Prevention: Fresh anti-corrosion package and pH testing.

Galvanic - A copper rad is one of the most noble metals. Iron will rust first as the anode and deposits will accumulate on the cathode, the copper rad. Brown deposits in a copper rad means you have this going on. When you introduce an aluminum component into the system, it becomes the anode vs the iron, and it becomes the sacrificial metal. Prevention: An excellent anti-corrosion package, and make the water as close to zero conductivity as possible, preventing as much transfer of electricity and ions as possible. Use only distilled water and pure antifreeze. Hopefully 50-50 blends used distilled water, but do they really specifiy? Keep it fresh with regular changes. Test the conductivity of the system and keep it as low as possible. The normal advice is 0.3V or less. Test it when new so you now where it started and change the coolant when it rises. You can never get or keep a water based system at zero conductivity, it is far too good at dissolving things, anything, something, even gases. The ultra-pure systems I worked with use multiple water purification steps, teflon pipes, and inert nitrogen gas blanket on top, and still "stuff" gets in. I am 100% positive that 50 year old iron cylinder block we all have has at least some rust / corrosion/ oxidation in it. And pure water will slowly dissolve some of that until it becomes conductive again, which is why you can never get the millivolt reading to zero. Some anti-corrosion packages coat the surfaces, like old Prestone Yellow. When that gets weak, the coating gets thin in one or more spots, and all corrosion gets focused on that spot, actually accelerating corrosion. The newer anti-corrosion packages get "consumed" as they fight corrosion, and can at times get depleted more quickly than you might assume. Some of these tend to go acidic when they get depleted, casing additional problems. Test: Millivolt meter, also prior pH meter Cleaning: If you have a old rusty block, run several chemical cleaning flushes thru it, rinse it with tap water, and then rinse it with distilled water, until the conductivity reading on your meter goes down and stays down. Ditto for my combination, an old marine block, which may or may not have ever had salt water in it, and a new aluminum radiator. I'll be cleaning & flushing....Prevention: Distilled water, or de-ionized water, pure antifreeze coolant, anti-corrosion package, regular changes when it deteriorates. Zinc anode in the drain plug is a good 2nd line of defense.

Electrolytic corrosion: Electricity. Static charges, bad grounds, alternators, electrical circuits, any number of things create electrical charges in the car, and sometimes they get into the cooling system. C3s are notorious for bad grounds due to the huge amount of grounds present. When a faulty charge causing circuit is operated, if the grounding circuit can not handle the flow, it will find the path of least resistance. Or cease to function well. A heavily worn / pitted trans tailshaft bushing is a common location due to a missing body ground. Remember the static eliminators in the bearing caps and the rubber axle straps that we drug on the ground back in the day? Sometimes these charges get into the cooling liquid. And it is never perfectly non-conductive, no matter how hard you try. Those rusty brown corrosion products will coat rubber surfaces internally and make that once rubber isolated component now part of an electrical circuit. The slightly conductive water becomes part of the electrical circuit. The common grounding point for this circuit is the heavy engine block, and it's ground strap, regardless of how this electricity got in. But what if you have a faulty electrical component that is actually creating static electricty by spinning? Those charges have to go somewhere. If the engine or it's accessories are causing the positive static charge, the normal flow will reverse, and it will enter the cooling system and look for a way out. What you want to avoid at all costs in this scenario is for the thin aluminum radiator or heater core from becoming a positive charged anode, which will quickly eat holes in it. Mid 90s Ford Taurus ('s?) were notorious for their AL heater cores dying in record short time. (I had two go within six months.) The AL radiator never leaked. There must have been some positive electrical leak in the dash area. The solution in this case is to ground the highly susceptible aluminum component to the frame. The 3rd core lasted >10+ years. The ground makes sure that component has a negative charge, and can never act as a positive anode, and it will not corrode. Electricity speeds up galvanic corrosion, but in the same direction. Like chrome plating. What you do not want is for the AL to become the positive charged sacrificial anode. Some have even campaigned for the installation of a one-way diode on this wire, to remove charges from the radiator, and prevent any feedback from something in the ground system, but I feel that is overkill. In a fresh system (aka: new car) with a rubber isolated radiator, with all new components, and fresh anti-freeze with almost zero conductivity, none of this would be necessary. But on an old car, extra prevention can not hurt. A bad alternator can easily cause this. Bad diode I believe? Identification: Test the conductivity of the coolant with your multi-meter, as each electrical system on the car is switched on, in turn, including the starting circuit. Obviously the easiest is to just check it with car off, then during starting, and then just turn on everything, and test it again. If any reading is high, start checking / cleaning grounds. Prevention: Keep coolant near zero conductivity, test occassionally. Make sure all your ground strap connections are good. Even test those connections under load. What else can you do? You won't know you have it until you get a leak. Anti-corrosion packages offer no help here. Only distilled water, and it is not prerfect. Component ground straps offers a 2nd or last line of defense, hopefully never required, but think of them like insurance. If some electrical item fails, and it certainly will at some point, do you really want your first indication to be a leaky $1000 AL radiator? Hopefully the ground strap is never needed and is pure overkill, but that is why they sell kevlar vests too. Add a diode to it if you are rally paranoid.

Doc:
On your car, I might be guessing, but I am thinking your problem could likely be electrical. Start testing: grounds, coolant, etc.