Aluminum Radiator and Water Pump - Zinc Anode?

[ckuske]

Hi All,

I'm getting closer to finally putting my cooling system back together.  I bought a new 3 row aluminum radiator, and an aluminum water pump.  Usually I'm a total purist on keeping things stock, but I thought these upgrades were worth it - I've read (hopefully the right material) that aluminum conducts heat better than brass, so the radiator will function better than the old style brass radiator.  As far as the water pump, it just looked good!

Now to my question - I stumbled across this Zinc anode to install into the radiator.  It seems like it would be worthwhile to preserve the aluminum parts in the cooling system.  Does anyone have any first hand experience with these?  Are they worth the trouble?

[Gary Lewis]

I don't have any experience with that anode, but I don't believe it is necessary if you keep your coolant up to snuff.  Modern coolants have corrosion inhibitors that prevent the galvanic corrosion that anode addresses.  But the inhibitors are used up over time, so it is important to change the coolant periodically.

[Lima Delta]

I've been using a similar aluminum rad for the last five years or so with no anode. I use Prestone 50/50 coolant with a bit of the concentrate to bump up the freeze protection a little.
Radiator works great and I haven't noticed any corrosion issues. It's a much sturdier rad than the stock unit I replaced. Looks good too.

I have read (but never seen) that the biggest and quickest trouble with corrosion in aluminum radiators occurs when the electrical system develops a fault where it grounds through the cooling system. The stray voltage can create an electrolytic reaction which will apparently ruin the radiator in short order.

LD

[Gary Lewis]

Having a current go through the cooling system is an absolute no-no.  And that is possible if the radiator support isn't properly grounded since the headlights and several other things ground to the radiator support in the original wiring scheme.  So it is important to make sure that the radiator support is grounded, and a ground wire from the fender to the radiator support would be a big help.

[Rusty_S85]

I never used the zinc anode before but if you do have more aluminum than OE I strongly suggest you upgrade your coolant.

Conventional green is ok for limited aluminum but once you start adding more aluminum in the form of heads, intake manifold and radiator you are better off running at least global gold coolant or dexcool as they are better at protecting aluminum.

I will be running global gold as it looks very similar to conventional green just considerably lighter and it wont hurt if there is a little conventional green left over.

[Rusty_S85]

Lima Delta wrote

I've been using a similar aluminum rad for the last five years or so with no anode. I use Prestone 50/50 coolant with a bit of the concentrate to bump up the freeze protection a little.
Radiator works great and I haven't noticed any corrosion issues. It's a much sturdier rad than the stock unit I replaced. Looks good too.

I have read (but never seen) that the biggest and quickest trouble with corrosion in aluminum radiators occurs when the electrical system develops a fault where it grounds through the cooling system. The stray voltage can create an electrolytic reaction which will apparently ruin the radiator in short order.

LD

You are talking about electrosis which isnt so much caused by bad grounds, GM trucks had this problem in the 80`s and why GM came out with Dexcool it was just the conventional green coolant with the design of the cooling system that was creating an electrical charge.  No amount of grounding the radiator or core support in those trucks would stop the electrical charge build up in the coolant.

You could take a 80s GM truck and pull the radiator cap off and stick the positive lead of a multimeter in the coolant and touch the negative lead to ground and get a voltage from the coolant itself.

[kramttocs]

I've got one of these in my cart for my next order. That way it doesn't plug up your drain.

[kramttocs]

Looks like Champion doesn't recommend dexcool.

https://shop.championcooling.com/articles/What-Coolant-Color-Do-I-Use

We get asked quite often what coolant we recommend for our radiators, and while we don't necessarily recommend one brand over another, we do have a type of coolant that we discourage using. We have found that the 'red' coolants, such as Dex-Cool and Toyota's Long-Life coolant, can clog our radiators, as well as promote leaks. We recommend the traditional 'green/yellow' coolant from most name-brand manufacturers, and to mix that coolant with distilled water at a 50/50 ratio.

[Gary Lewis]

That's really important info to know, Scott.  Thanks!

So Dex-Cool is a no-no.

[kramttocs]

Since I am in the process of doing a few flushes I figured it was a good time to re-research some of this

Most of what I found was on forums but a lot of the Mustang and Corvette owners with aluminum radiators are using and recommending the green. Take it for what it's worth.

Dewitt had this to say:

The key to maximizing the life of an aluminum radiator is not so much the coolant brand as it is the water type. All coolants sold today will protect the aluminum radiators adequately however distilled water must be part of the package.

I ordered the cap with anode today but without time passing, won't be much to report on regarding it.

[kramttocs]

While not directly related to the topic, I would also mention that those with aluminum radiators (or even without) might want to consider a 90 degree petcock. I installed the one I bought from Amazon this evening and Cory found one on cjponyparts.
Since it's more important to change the coolant regularly with aluminum components, might as well make it easy on you.

[Gary Lewis]

Do you like the one from Amazon?  I'm a couple of years from changing the coolant, but should go ahead and get that petcock so I'll be ready when the time comes.

[kramttocs]

So far. Seems well made and the wings are solidly attached without fear of them spinning.

I used Permatex Seal and Lock on it so will give it a few days before filling.
It didn't thread in very far and with it being directional, there's always the fear it will just land wrong but it worked out well in my case.

After dealing with the original last night which was a real pain trying to get the last drop out without letting it just dribble into the core support, I am more than happy with the prospect of this. Now just hoping no leaks.

[ckuske]

Thanks for this, I didn’t know about this!  Sounds better than replacing the petcock, and it seems like cheap insurance.

This is the radiator I bought, I’m painting the radiator support this week so hopefully I can test for it soon.

https://www.championradiators.com/Ford-F-series-truck-radiator-1980-1984

[Gary Lewis]

I bought the big brother to that one, a Champion 4-row.  When you get yours check the neck carefully where the cap seals as mine was dinged there and I had to file it out.

And, if you don't replace the petcock make sure to check that it is installed correctly.  Mine wasn't tight in the radiator and it leaked.  But, those are tapered pipe threads and you can break the radiator if you tighten it too much, so put some sealant on it and snug it up good.

[ckuske]

Thanks Gary!  (And Scott!) for this as well. After all the rust removal and sanding, I’d hate future flushed to drip onto the rad support.  Seems like you could hook a hose up to it and drain into a bucket.

I assume the size of the petcock  you guys are referring to is 1/4”-18 NPT?

[kramttocs]

ckuske wrote

 Seems like you could hook a hose up to it and drain into a bucket.

I assume the size of the petcock  you guys are referring to is 1/4”-18 NPT?

Precisely! I stuck a scrap piece of hose on the one I installed and it has a nice tight fit. Seeing the hose drop straight into the five gallon bucket and knowing you won't have coolant run down your arm while loosening the drain stop anymore or spray all over everything until you get the funnel just right...it's the small things in life

Yes on the size

[Gary Lewis]

I'm sold.  I ordered the one from Amazon for $10.49 with free shipping.  CJ Pony Parts wants $19 for shipping a $10 part, and that just torques me off.

[Machspeed]

kramttocs wrote

Since I am in the process of doing a few flushes I figured it was a good time to re-research some of this

Most of what I found was on forums but a lot of the Mustang and Corvette owners with aluminum radiators are using and recommending the green. Take it for what it's worth.

Dewitt had this to say:

The key to maximizing the life of an aluminum radiator is not so much the coolant brand as it is the water type. All coolants sold today will protect the aluminum radiators adequately however distilled water must be part of the package.

I ordered the cap with anode today but without time passing, won't be much to report on regarding it.

When I had half my engine apart this past Summer due to a coolant leak at the intake manifold, I did a lot of surfing regarding coolants. What you have posted Scott was the consensus of everything I read including the Dexcool.

   

[Gary Lewis]

This 2008 article entitled GM settles lawsuits over engine coolant problems says:

The lawsuits, first filed in April 2003, alleged that Dex-Cool degraded manifold gaskets and other engine components and sometimes formed a rusty sludge that clogged cooling systems and caused vehicles to overheat.

The article says that GM agreed to pay up to $150,000,000 but said "GM has denied any wrongdoing and said the settlement was aimed at avoiding further costs and saving time".

But apparently Dex-Cool continues to be sold?  This article from 2017 shows there were still class action law suits going on and people were trying to get a national one going against GM.