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Bloo's not-quite-scientific antifreeze foaming test.


Bloo
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Late last year as I was getting ready to head to Wisconsin in the 1936 Pontiac, I was going through the lubrication chart, making sure everything was getting greased and oiled. I decided to change the coolant. It was getting almost 3 years old, a bit longer than I usually leave it. Unlike the rest of my cars, this had the old fashioned green coolant in it, mainly because even though I had changed it before I never had the opportunity to rinse it out completely.

 

Like a lot of other prewar cars, the Pontiac has an "open" system, meaning the coolant is not under pressure. It also has a packing nut on the water pump for a seal. Systems like this are known for having a foaming problem when using the typical ethylene glycol coolant instead of water. The foam goes out the overflow tube, and then the engine runs low on coolant and boils over. There are several old threads about it. Some forum members, like @edinmass ,@Grimy and others have figured out additives to control corrosion when using plain water that work fine in the climates they live in. That won't work for me. The climate here can have sudden unexpected hard frosts, and broken engine blocks were common in the old days when people were caught off gaurd by a sudden cold snap. I need antifreeze for coolant.

 

I had no foaming problem though. I figured I was probably getting away with it because the Pontiac has a cross flow radiator(!). Unlike most prewar cars, any foam would have to pass through the core before it could get near the overflow tube. Ignorance is bliss I guess.

 

So I went ahead and rinsed the whole system out with distilled water and changed the coolant. In the interest of making no radical changes before a trip I decided to stick with the old fashioned green coolant. I picked some "Oreilly conventional green antifreeze and coolant" which said it was for use in "Ford and Chrysler: 2000 and earlier, GM and all other makes 1995 and earlier", mixed it 50% with distilled water and put it in. On the first drive the temperature shot up suddenly and it boiled over badly in the middle of a bridge about 5 miles from home. It was hotter than hell when I pulled into a convenience store on the other side. I got some food while I waited for it to cool down and then bought a gallon of their horribly overpriced coolant. It was Havoline "conventional antifreeze/coolant" (green) "for older autos and light duty trucks" in 50/50 premix. A gallon wasn't enough. I had to go back and buy a second one. I had a new problem and the Flathead Reunion was looming. This car had been working fine for literally years. Bah!

 

Over the next few days I tried all sorts of things. I checked it for combustion gas in the radiator like you would get with a blown head gasket. It passed. I retorqued the head anyway. I checked the packing nut on the water pump and gave it a squirt of water pump grease. It was fine. These things had already been done, but I went over them again anyhow.  A car that is leaking combustion gas into the radiator, or sucking air through the packing nut will have an uncontrollable foaming problem.

 

With those things out of the way I was staring to seriously suspect the coolant. I had to check it for a bubble though. I got it warm pointed uphill and observed the coolant flowing. I bought more Havoline "conventional antifreeze/coolant" (green) "for older autos and light duty trucks", this time concentrate, and mixed it 50-50 myself with distilled water. The next day I threw 4 gallons of this home-mixed Havoline coolant in the floorboard and headed about 60 miles upriver. There is a big hill on that highway. I kept pulling over a lot and checking the level. Usually fine, sometimes it lost a little but not much. At one point I pulled over at a walmart and it pushed out about a quart. sometimes it didn't need anything. Then later on the way back it suddenly pushed out a gallon and boiled.

 

There really isn't anything to blame at this point but the coolant. I started searching for anti-foaming additives. Since apparently this is a non-problem in modern pressurized systems, none existed. I eventually found a Shell Rotella coolant that advertised it had a "robust anti-foaming additive" or something like that. It was discontinued or rebranded and none was available. That lead eventually to another Shell coolant that had a reference to an ASTM test for foaming that it passed. There is no Shell bulk plant locally to ask. The only outlet online that had any was selling it in bulk. You had to buy 200 gallons or something like that.

 

That led to reading datasheets for antifreeze. There are not just two or three formulas anymore. There are probably at least 20. No silicates, no Phosphates, Low this, high that, silicates but no phosphates, HOAT, OAT, IAT, 2-EHA, AMAM, include this, delete that, coolants meant to have their additives replenished periodically, coolants that are not meant to have anything added, and so on. Different additives or the lack of them are needed to satisfy warranty requirements on different brands of engines. This doesn't just include cars by the way. Also over-the-road trucks, compressors, generators, heavy equipment, the list goes on. It is almost as if you can choose your coolant ingredients a la carte. Worse the color means *literally nothing* today. Green or pink could be almost anything. There are efforts underway to have a color standard, but right now warranty accepted coolant for one engine could be purple in one brand, yellow in another, and pink in yet another. Also some formulas can be bought in multiple colors from the same source. It's dizzying.

 

 

Edited by Bloo (see edit history)
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I mentioned datasheets. They are online for several brands of coolant. They are usually several clicks deep for each product as if they meant to waste your time. Sometimes foaming is mentioned, sometimes it isn't. Some brands have really crappy incomplete datasheets. Some, like Prestone have good datasheets for their truck and industrial products, but any product intended for a car just has a bunch of useless marketing babble. Then there is Valvoline/Zerex. Their datasheets are largely complete and useful, all the way down to their cheapest product.

 

About that ASTM test for foaming. It is ASTM D1881-17. I looked it up. It turns out they would like to sell you a PDF of it for $48. I did find a copy online somewhere. It references a bunch of other ASTM standards, all of which have PDFs online for sale for similar amounts. That is a non-starter. In threads about coolant, usually doubt is raised about the ability of some formulas to protect the metals used in older cars. It turns out there is an ASTM test for that too. It is ASTM D2570-16 Like the foaming test it references a plethora of other ASTM standards that could make you poor in a day over some PDFs. In the better datasheets though, the results of these tests are given, and you can compare them. How to interpret them is a little tougher.

 

The top four scores of everything I looked at included 3 Valvoline/Zerex products and one Shell product. But how do we interpret the scores? If it passes ASTM D1881 does that mean the foaming is negligible and I am splitting hairs by comparing scores? I don't know.  A passing score is 150ml of foam and a 5 second break time. Without further ado, here are the top four.

 

 

#1. Shellzone Multi-Vehicle ELC. 30ml foam. Less than 1 second break. Yellow in color. I literally could not find this to buy in gallons, even online. The ASTM D2570 corrosion test was listed in the datasheet as one of the standards that it meets, but no further information was given about how it did in the test.

 

FvjaIjE.jpg

 

#2. Valvoline/Zerex G-30. 35ml foam, 1 second break. Purple in color. (I did not pick this one).

 

YQADnAu.jpg

 

Why did I not pick this? While available locally, it was not in stock in any quantity. I wanted something common if possible that I could just buy far from home if I needed more. Also, it is only available premixed and that drives up the cost. Thirdly, it did not do as well as some others on the corrosion test for copper.

 

In ASTM D2570, the corrosion test, they use "coupons" of the various metals used in engines and circulate hot coolant over them. The limit for copper is 20mg of metal loss. This scored 16.4mg. The limit for brass is 20mg. This scored 4.9. The scores for all other metals in the test were very low. So, how bad is 16.4? Is any passsing score negligible loss? I don't know. I do know some of the others scored better.

 

#3 Valvoline/Zerex G-40. 40ml foam, 1 second break. Pink in color. (I did not choose this either).

 

INEE6B2.jpg

Why not this one? It's ASTM D2570 corrosion test results on solder. The limit was 60mg for solder, this scored 24mg. Is that bad or am I splitting hairs? I don't know The loss on all other metals was vanishingly small. There was more of this on the shelf locally but still not a lot.

 

#4 Valvoline/Zerex G-05. 35ml foam, 2.1 second break. Pale yellow in color. I think we have a winner.

 

xDfFD05.jpg

 

This looked like a good place to start. Metal loss was vanishingly small for all metals. It is available in concentrate, and is in stock in quantity at both Oreilly and Autozone. It has a 2.1 second break though. If you think about it, if you are constantly making more foam, that might be twice as much foam as the second place Valvoline/Zerex G-20 because the volume is the same (35ml) and the bubbles take a little more than twice as long to pop (2.1 seconds vs 1 second).

 

If anyone wants to see datasheets, they can be accessed from the pages below. Direct linking the PDFs proved impractical. Scroll down.

 

https://solutions.shell.com/us/products/ShellZone_Multi-Vehicle_AntifreezeCoolant__228C8524

 

https://www.valvoline.com/en/zerex-G30-antifreeze-coolant/

 

https://www.valvoline.com/en/zerex-g-40/

 

https://www.valvoline.com/en/g-05-antifreeze-coolant/

 

Hoo boy... I didnt mean it to be this long... more coming....

Edited by Bloo (see edit history)
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I never would have dreamed that going from one brand of antifreeze to another would cause such a headache. Someone converted June bug to a pressurized system so I've had no problems but will be watching what you come up with for a cure. 

Thanks for posting on this.

 

 

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Testing to the ASTM standards was out of the question. I can't afford the standards, let alone the standards referenced by the standards, or the standards referenced by those standards, never mind the lab equipment.

 

What are we going to do then? Simulate real life conditions as much as possible by heating the coolant to 200F and beating the crap out of it with an eggbeater for two minutes.


 

KgbZJaS.jpeg

 

 

kNGNDIy.jpeg

 

 

Now right up front there is a bit of a problem with this method, that being that the coolant will start cooling down almost instantly while being beaten. Still, maybe we can tell something. Onward!

 

Today's contestants are:

 

1) Havoline Conventional (green), 50/50 mixed with distilled water. Possibly with a little Oreilly Conventional Green still mixed in. Drained directly from an recalcitrant Pontiac.

 

2) Prestone All Vehicles. Mixed 50/50 with distilled water.   @37_Roadmaster_C had a some Prestone left over from his wife's car, and I ran off with a couple cups. 

 

3) Prestone DexCool Mixed 50/50 with distilled water.  As used in my other cars.

 

4) Valvoline/Zerex G-05. Mixed 50/50 with distilled water.

 

Here is the Havoline Conventional, after one minute of the eggbeater on high:

 

TMqTUq4.jpeg

 

Two minutes, at the moment the beater was pulled out:

 

VtGQuxK.jpeg

 

Five seconds later:

 

xvVkAjP.jpeg

 

10 seconds:

 

5z93fJE.jpeg

 

15 seconds:

 

Qte5Si3.jpeg

 

20 seconds:

 

v0hkWCp.jpeg

 

25 seconds:

 

NbEhoJW.jpeg

 

30 seconds

 

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35 seconds:

 

5stAqQy.jpeg

 

40 seconds:

 

hHIxiC9.jpeg

 

45 seconds:

 

9z6ZmwO.jpeg

 

 

 

Edited by Bloo (see edit history)
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Next up, Prestone All Vehicles. One minute in with the eggbeater:

 

FEZL26x.jpeg

 

Two minutes, just as the eggbeater was pulled out:

 

NqBpSty.jpeg

 

5 seconds later:

 

vKYEXcz.jpeg

 

10 seconds:

 

ekcHFuu.jpeg

 

 

15 seconds:

 

BeL0ad7.jpeg

 

Well, that's a difference!

 

Next up is Prestone DexCool, or rather it would be If I had any pictures. I did this experiment twice. The first time I couldn't manage the camera in a timely manner, and so the next day I got @37_Roadmaster_C to come over to my place and hold the camera. Unfortunately the sample of Prestone DexCool leaked out of the container overnight. It's performance in the original run was slightly better than Prestone All Vehicle, but hardly enough to mention.

 

Next up, Valvoline/Zerex G-05, one minute in with the eggbeater:

 

RXRqBKx.jpeg

 

Two minutes in, just as the beater was pulled out:

 

8Jb0GGS.jpeg

 

5 seconds later:

 

f9Ce2VM.jpeg

 

10 seconds.

 

J7MYqfh.jpeg

 

15 seconds:

 

quzctp2.jpeg

 

20 seconds:

 

YPKbCPg.jpeg

 

This is clearly better. It barely made any foam even while the beater was running. It would have been nice to try a bunch more samples, but I found what I needed to solve the problem for the trip and so I stopped here.

 

Feel free to expand on this!

 

 

 

Edited by Bloo (see edit history)
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@Bloo,

 

First off thanks for showing us your experiment of the different brands and types of antifreeze. It sure is amazing the different outcomes that you had discovered.

 

Please keep us informed how the trip goes with the use of the Valvoline/Zerex G-05.

Edited by Tom M (see edit history)
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I used to run a lab where we ran certified testing, but not these.  ASTM, ISO, DIN all sell their test standards.  You have done some good detective work and have the actual test results.  They tell you what happened on the standardized tests. View the results as the likely relative performance in the car, but "your mileage may differ."

Your home made one is not bad at all - the main issues are the viscosity change as the temperature changes (I'm nearly certain the ASTM tests will run at controlled temperature to greatly reduce this) and mixing the same way each time.  I'd suggest marking the inside of the bowl with level lines.  Fill to the same line each time and note the height of the foam, as well as timing the mixing and foam decay times.

As I think you understand, colorant is added and means absolutely nothing intrinsically.

If you want to change to a different problem, you could try an alcohol/water coolant.  However, it requires routine checks to replenish against evaporative loss.

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While the homemade "heat the liquid and use egg beater to agitate" test has shown some interesting results, I don't think it would be scientifically analogous to the constraints anti-freeze/coolant goes through in a non-pressurized engine. The coolant circulates by a slight pressure (2-3 lbs) generated by the water pump impellor and typically sits in radiator for a while as it drops from top to bottom. Any foam bubbles in coolant would rise to top of radiator during this time and escape through the overflow typically. The question is why would temperature of coolant rise? If circulation system is running properly, you can usually see coolant coming into rad tank from engine and if the coolant is running clear at that point, I'm not sure "foaming" is creating an issue. Since the coolant expands when heated, I leave my rad filled about 1-2 inches below neck when cold and that avoids overflow when heated. I hope there is a fluid dynamics specialist on this forum who can chime in on what might be the issue here. I ran the green stuff at 50% in my 1931 Chevrolet stove bolt 6 for years without any issue of any sort, and never changed it, it was as clear and effective after 10 years as it was when I put it in. Is it possible your coolant change led to an airlock somewhere?

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I have no insights about foaming. When I was a kid I worked on a 1936 Pontiac that had overheating issues. I really had no experience but I said I could fix it. Straight 8 engine that ran beautifully. Tried all kinds of things  but no luck. Eventually came to realize the water distribution tube had rotted away. To big of a job for me but my grandfather told me nothing pulls heat as well as water. Freezing was the problem but read you could add alcohol to combat that problem. Worked better but still had the long term issues with overheating. Just a memory but loved how good of an engine and car it was. Good luck.

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Although I've never tried it, *low-silicate* anti-freeze is reportedly good at minimizing foam.  I never see it on the shelves in the Bay Area, however.

 

My 1934 and 1936 Pierces (and my 1934 Buick of happy memory) had their radiator fillers under the hood at essentially the top of the radiator and at the end of an ell.  Because you couldn't see coolant until it was within half an inch of full, it was necessary to top these cars off hot after the bulk of the coolant had expanded.  On earlier cars with exterior fillers, I top off to just covering the core.

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Very interesting discoveries here Bloo.  The differences in foaming are remarkable and as you demonstrate, quite obvious.  Have you contacted any of the manufacturers directly for their inputs on formulations best for old cars?   

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Interesting results from your tests.

 

Have had good luck with Zerex Original Green. Used exclusively on my '26 Buick, '26 T and '30 Model A.  Never had any foaming. I buy full strength and mix with distilled water.

 

 

IMG_3387.jpeg

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5 hours ago, MikeC5 said:

Very interesting!  I'm a little confused though as to which is the first one tested with lots of foam?

 

It was drained from the car.

 

A few days earlier the car, which had been working fine for about 3 years, was drained, rinsed out with distilled water, and filled with "Oreilly Conventional Green Antifreeze and coolant" for Ford/Chrysler 2000-earlier and 1995-earlier GM/others. It was mixed 50/50 with distilled water. It almost all blew out out on the ground 5 miles later. It was refilled with Havoline's "conventional" formula "for older autos and light duty trucks", continued to have the problem, and was refilled with a LOT more of the Havoline over the next few days.

 

It was Havoline. There could have been traces of the Oreilly coolant in it. There couldn't have been much Oreilly left by the time this test was done. Maybe some residue. I'll go edit the first post to match the exact verbage on these bottles.

 

The foaming problem has been widely reported with "conventional" formulas in open systems designed for water. Somehow I was getting away with it without any issue until this last change.

 

4CPyA7c.jpg

 

gagFesS.jpg

 

 

 

 

 

 

Edited by Bloo (see edit history)
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I always find beating the wife much more enjoyable than beating antifreeze.............. 🤩

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37 minutes ago, AzBob said:

Interesting results from your tests.

 

Have had good luck with Zerex Original Green. Used exclusively on my '26 Buick, '26 T and '30 Model A.  Never had any foaming. I buy full strength and mix with distilled water.

 

 

IMG_3387.jpeg

Thanks for posting, success stories encouraged!

 

Valvoline/Zerex's datasheet says this one had 75ml of foam with a 2 second break time, compared to 35ml of foam with a 2.1 second break time for G-05. Both pass ASTM D1881 with plenty to spare as the upper limit is 150ml of foam and a 5 second break time.

 

This one also passed the ASTM D2570 corrosion test with flying colors (very low corrosion).

 

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1 hour ago, AzBob said:

Interesting results from your tests.

 

Have had good luck with Zerex Original Green. Used exclusively on my '26 Buick, '26 T and '30 Model A.  Never had any foaming. I buy full strength and mix with distilled water.

 

 

IMG_3387.jpeg

Not sure if I am doing the right thing, but I do exactly the same as AzBob, green Zerex diluted with distilled water.

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All kidding aside, I found the test interesting and informative. I wonder if one adds cutting oil to the mixes above will it alter the results. Nothing ventured, nothing gained. 

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5 hours ago, edinmass said:

All kidding aside, I found the test interesting and informative. I wonder if one adds cutting oil to the mixes above will it alter the results. Nothing ventured, nothing gained. 

@edinmass you've talked before about cutting oil as an additive.  What dosage rate do you recommend?

 

The previous owner of my Paige was a fervent believer in soluble oil, and it seemed to reduce heat transfer from the cylinders and contributed to a "sludge" which was captured by my stocking filters.  I'm sure he grossly overdosed it.  What's your recommended dose (ounces per quart of cooling system capacity) and make up dose?

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With straight water I run four to six ounces in a cooling system by size.......with anti freeze I am not sure it’s a good idea. There is a DOW chemical additive to reduce foaming......and it’s like an eye dropper full for an entire car. I’m not sure if foaming in non pressurized systems is totally figured out..........chemical contamination, cracked block, bad head gasket, water pump air suction, water distribution tube.......what I do know is if the block isn’t clean....and I mean spotless as well as a radiator flowing correct gallons per minute........it’s a useless battle. The change of coolant to something new and having an issue is strange. As usual, I would start from square one.

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9 hours ago, edinmass said:

With straight water I run four to six ounces in a cooling system by size.......with anti freeze I am not sure it’s a good idea. There is a DOW chemical additive to reduce foaming......and it’s like an eye dropper full for an entire car. I’m not sure if foaming in non pressurized systems is totally figured out..........chemical contamination, cracked block, bad head gasket, water pump air suction, water distribution tube.......what I do know is if the block isn’t clean....and I mean spotless as well as a radiator flowing correct gallons per minute........it’s a useless battle. The change of coolant to something new and having an issue is strange. As usual, I would start from square one.

@edinmass "four to six ounces in a cooling system by size" -- OK how much for a 32 qt Pierce 12 system vs a Model A system?

 

We can agree that perhaps with a complete, correct, rebuild of engine and cooling system components there's a much lesser chance of encountering foaming in an unpressurized system.  That takes care of 0.5% of us.  Now for the other 99.5%, we are looking for successful ways of reducing or eliminating foaming, whether by anecdote or by some semi-scientific testing.  There are many other variables as well--relating to make/model of vehicle, type of driving, etc.

 

My comments in an August 2019 thread have been linked in this one.  I'll summarize:  When I bought my 1934 Pierce in 2006, it had less than 500 miles on a block boilout, new radiator core, water pump rebuild with modern seals rather than packing, no chance of lower radiator hose collapse because it had the correct steel tubing with two 4" sections of hose connecting the lower radiator outlet to the pump inlet, AND 50% Peak [brand] traditional EG anti-freeze.  Driving at 55-58 mph to Redmond, OR (about 600 mi) every pit stop required 1-1.5 gallons of coolant.  Upon my return, I flushed the (unnecessary for me) anti-freeze and commenced using distilled water + Pencool 2000, and the coolant consumption was no longer an issue.  Now, almost 16 years and 17,000 miles later, this car needs a top-up of less than one quart every 700 miles or so.

 

That solved MY problem but only because I don't need antifreeze.  Many more of us must use antifreeze.  Ed and I have a good friend in Michigan who has multiple Pierces and is a highly skilled Pierce tech--and he installs antifreeze only over winter and flushes his cooling systems every spring.  Isn't there a better way?

 

@Bloo has an excellent thread going here and I encourage everyone to add their experiences, both successful and unsuccessful.

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When I bought my PA the seller had a 50-50 mix of unknown af in it for the winter.

He suggested that I drain that after shipping because of foaming issues.

Well, I didn't and the first drive of any distance it puked a bit when I slowed to a stop from about a six mile drive at speed.

Just enough that I could see it, no boil over.

I went back home with no issues and the radiator still showed enough to make me happy.

No issues since.

I find Bloo's experiments quite interesting, I wish I had his ambition.

I am saying to myself that I will reference his results next time I change out my af.

I don't own an egg beater.

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  • 5 months later...

Boo I just discovered this thread and applaud your documentation and thank you for sharing your experince with us. Our 1914 Chandler with it original radiator still in use has been a challenge for me to keep cool. The car spent its entire life in northern Iowa where it stays much cooler that its new home in southern California. Here we don't need anti-freeze so straight distilled water with an anti-corrosion additive is my normal set up. After sorting out the water pump and flushing the entire cooling system with Evan-Rust I've currently settled on a combination of distilled water and a bottle of Redline Water Wetter. The Wetter is supposed to control the foaming which in effect increases surface contact of the water and provide anti-corrosion. So far the results have been pretty good.

0000116_waterwetter_464.png

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Wow Bloo, what an interesting post.  I've run mostly NAPA green in my '36 Master Six for the 57 yrs I've owned it and have never knowingly had a problem with foaming. I did make a modification to the radiator 20 yrs ago though: had my radiator guy put a new neck on it that will take a 3-4 lb cap. Really helped with overheating in very hot weather (90s) when in traffic or going up hill. One key is to not overfill the cross flow radiator; fill only to the outlet hose level. Seems counterintuitive but that's how they were designed (as you well know).  Don't know how they ever got around in the Deep South with these cars back in the day.

 

You going to this year's Flathead Reunion? I plan on making the 1,200+ roundtrip drive in my coupe. Hope to see you there. Still problem solving with the Ford.

 

Bob

 

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17 hours ago, 29 Chandler said:

The Wetter is supposed to control the foaming which in effect increases surface contact of the water and provide anti-corrosion. So far the results have been pretty good.

I like that stuff, and used to sometimes add it to antifreeze, though I think antifreeze already has additives like that. A friend of mine used to use it in his race car. Mixed with water, it does drop the temperature a few degrees, at least if you are running above the temperature of the thermostat, or don't have a thermostat! I don't dare leave water in a car here though, it can get forgotten and the cold weather does come suddenly.

 

 

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15 hours ago, Bob Shafto said:

Wow Bloo, what an interesting post.  I've run mostly NAPA green in my '36 Master Six for the 57 yrs I've owned it and have never knowingly had a problem with foaming. I did make a modification to the radiator 20 yrs ago though: had my radiator guy put a new neck on it that will take a 3-4 lb cap. Really helped with overheating in very hot weather (90s) when in traffic or going up hill. One key is to not overfill the cross flow radiator; fill only to the outlet hose level. Seems counterintuitive but that's how they were designed (as you well know).  Don't know how they ever got around in the Deep South with these cars back in the day.

 

You going to this year's Flathead Reunion? I plan on making the 1,200+ roundtrip drive in my coupe. Hope to see you there. Still problem solving with the Ford.

 

Bob

 

 

I have had pretty good luck running mine in hot weather, although it does run 190F. It does not matter if there is a thermostat as it would always be open. I am changing my water tube and hope I can drop that down a little. I still have the open system. I understand the Eights had 4 pound pressure systems from the factory. As I recall Pontiac says you can run an extra quart above the petcock (cold) in the summer, but mine won't hold that much, maybe 2 extra cups, and that will bring it clear to the top when it is at 190F.

 

I don't think I can make it to the reunion this year, but I am still trying to figure out if I can. Maybe. I won't be bringing the 36 if I do. I am in WA, and PA is just too many days on the road. If I do it I'll either be flying out or driving a modern car on the interstates to save time. I'd love to see your coupe. So far there have been no other 36s at the reunions I have come to.

 

 

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