Short history on'70 383HP Plymouth....Two years ago, converted original 22" radiator 2 row to 3 rows. Added 50/50 Zerex (original formula, ethylene glycol) and distilled water. One year ago, I flushed and added new mixture of the same. Removed radiator in July'14 for engine rebuild and found white,crusty deposits starting to collect inside the radiator. The radiator shop told me it was from using "junk" antifreeze and it was reacting with the solder. Radiator shop said to use Prestone. I've been using the Zerex in other cars,trucks, equipment for over 20 years with no issues. Anyone know what's going on or what brand antifreeze to use?

You used the good original "green" stuff if I'm reading this right (I forget if that is zerex or prestone) & distilled water so that is perfect. all I can add is people have said to avoid the orange death (dexcool?). OT People have added several drops of liquid dish soap for a poor mans' water wetter and a bit of baking soda as an acid neutralizer. I would flush it out good & refill with distilled water/original green antifreeze (refresh me, is the green P or Z ?) just like you originally did & continue searching for a good answer on where the corrosion came from, if it is just natural deterioration. PS that was a brass radiator correct?

I bought the local stuff and it started turning acidic. I flushed it and added Prestone...couldn't get the pH over 8. I am convinced it was the "distilled" water. I think the bottle manufactruers just fill it up from the tap and sell it as purified. Those white specks you saw might be broken down mineral deposits in your mixture.

I went ahead and bought de-ionized water and pure Military Spec Ethylene Glycol...so pure...that it was clear in the container. I added the green dye myself. My pH is now 9.x and mixed to 50/50. I wouldn't know the first place to look for pure ethylene glycol in the U.S. but if you can track it down with de-ionized water (think steam irons for clothes).

If you have any aluminum parts on your setup, do yourself a favor and run a few sacrificial anodes. I got mine from Boatzincs.com and I also run a radiator cap with a spring attached to the cap connected to another sacrificial anode there (eBay) it free flows in the coolant of the radiator.

I wonder too if there is a difference , last summer my 07 Caravan sprung water pump bearing blew out the coolant, I topped it off with the green Advance Auto Parts coolant, since I have a unlimited drive-line warrentee I went back to the dealer and got a new pump installed under warentee but they tried to charge me extra for a flush since I contaminated the system with the green stuff,the dealer said the green antifreeze is really bad for the the system anyway I refused to pay for the flush , I could be wrong but I did not ask for a flush so I did not think it was mine to pay for.

RapidRobert,
Yes,the Zerex is green. Don't know the color of the Prestone. And yes, the radiator is the brass type.

I use Prestone extended life with great results. Mixed with Walmart reverse osmosis water. I keep it in 2-3 years between changes and the visible insides of the radiator looks as new.

Still I would not expect to have significant problems with standard green Zerex changed every year or two. As others have posted there may be something else going on. Problems with the water, stray electric current caused by weak ground or something else. I'd check all grounds to make sure they are clean, tight and plenty heavy. From memory, OE had heavy cable to the block and minimum 10 gauge to the chassis (radiator support?). Another ground from engine block to front frame rail or K frame would not hurt. The radiator should be grounded to the support by clean contact with the bolts or radiator support.

I've never used one, but some folks have good luck adding a sacrificial zinc anode in place of the lower radiator drain. It gets eaten up first by any electrolysis and protects the rest of the system.

I notice the longer the car sits in between drives the more crummy the antifreeze looks, also anything under 50/50 mix seems to build crud in the old radiators! I usually mix 60/40 to about 70/30 antifreeze/water and everything stays clean.

I agree on both points...

Prestone, and proper grounding...


Got 20 years on a 3-core...

Looks new...

Regarding possible electrolysis in your coolant system, I was directed to place one probe of my voltage meter in the coolant and the other probe grounded to my engine block or negative battery cable. The radiator shop told me if you see .4 volts or more, you have an electrolysis problem that you need to solve (I think that means a grounding issue).

This web site contains info on electrolysis and sells parts to help combat it.

http://www.ve-labs.net/

I checked the same thing with the voltage..I had .435v ...I wanted the sponge from VE labs but they dont have them in stock anymore...Also wanted the heater hose in-line filter to help the system.

I will be adding this to my Barracuda (already added to my Jeep):
http://www.fleetfilter.com/filter/wix-filter-bases/24019.html

This is the filter I am using on both vehicles:
http://www.fleetfilter.com/filter/wix-coolant-filters/24070.html

On my Jeep, I ran the heater feed hose into the filter base and then to the heater core. I plan on doing the same thing for my Barracuda once I get it all back together again

Going by the color is confusing. A few years ago I started looking at the labels and the spec sheets.
Motor magazine's August 2004 Coolant article was helpful. Here's a brief summary.

The first characteristic is easy. The main component of the anti-freeze will either be Ethylene Glycol or Propylene Glycol. The latter is less toxic to animals. Both need corrossion inhibitors.

The next part is the corrosion inhibiters..
Traditional coolant had Silicates and Phosphates. They protect exposed surfaces quickly. Some concern about Phosphates and hard water causing problems. Good reason to use filtered or distilled water when possible.

OAT coolants use Organic Acid Technology. They are supposed to hold up longer (eg. extended life) but they also take a long time to become fully effective.
Dexcool approved OAT's had in them several inhibitors including the two OATs;
sebecate and 2-ethylheconic acid (2-EHA).
2-EHA works well in hard water and is protects cast iron. On the other hand, it softens plastics and IF the coolant level drops so the cast iron is exposed, it allows fine powdered rust to form on iron. This then washes into the radiator. Not so good, and apparently was a problem for some cars with faulty coolant recovery systems.

Honda and Toyota decided (around 2004) to specify their OAT coolant as sebecate without 2-EHA. Motor magazine reported that tests of soldered copper radiators showed significant weight loss with the coolant. Definately NOT for cars with copper radiators or heaters!

The next group of inhibitors are in the HOAT coolants. HOAT stands for Hybrid Organic Acid Technology. But the HOATs don't use the 2EHA at all, but benzoate instead. Because of the problems Chrysler and Ford saw with 2-EHA, they adopted the G-05 HOAT standard, already being used by some European car manufacturers. This has low silicate and no phosphates in it.

My conclusion was to avoid any coolant labeled OAT. This was because both my vehciles have copper heaters and radiators. One has aluminum waterpump and intake, the other cast iron water pump and intake. So I use either a HOAT or a traditional coolant with both silicates and phosphates.

At one time wasn't there only two or so plants making antifreeze and one was damaged sending prices up?

Yup. I remember that. I believe it wasn't an anti-freeze manufacturing plant but where the ethylene glycol itself was being produced.

Here's a link to a pdf chart for which coolant has what, what its for, and what color it is dyed. It's just for the Valvoline-zerox brands. I've been buying the 'maxlife' which is a conventional inorganic coolant.
http://www.whitfieldoil.com/downloads/ZerexAntifreezeLineupChart.pdf

That chart is from 2003. Some folks at on the oil forums e-mailed valvoline in 2012. Maxlife is now dyed yellow, but otherwise seems fairly similar to earlier incarnation.
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2491912/2

I've had GO5 in my B'cuda with aluminum heads and radiator for many(6-8) years. The coolant looks like brand new as does the radiator tubes that are visible.Plus it has not froze yet...lol...I live in WI!!