Lower half of radiator stays cold while driving

[bavArian]

Hello everyone,

I took my A for a few trips in the last few days and, while it runs well now, I still have a problem with an overheating engine when driving uphill for extended periods of time or going faster than ~ 45 - 50 mph. (at an ambient temp. of ~70 °F)


First off some info:

- ran 50/50 water/antifreeze
- switched to straight water with diswasher tabs today
- timing was checked with a timing light, it's spot on; manual advance works
- no bubbles in the water with the engine running, just a constant stream of water from the pump
- carb is fine now, jets are within specs


What I noticed is that immediately after stopping when the car starts to overheat, the upper half of the radiator is hot but the lower half is relatively cool. It only gets hot 30 seconds (or more) after stopping.
I understand that the water should exit the rad cooler than it enters it (duh) but is it normal for the water to cool down so much? It seems to me that the heat transfer from the water to the rad is considerably worse in the lower half of the radiator. Idiot-me didn't think to check if the outlet of the rad is hot or cold, will do that on the next run.


I took it on a trip of about 30 mls today with the diswasher tabs in it and then emptied the rad. The water had a yellow/brownish hue and didn't look clean. I assume that's just dirt/grease from the past that's slowly being dissolved by the hot water?
Might add that the antifreeze-mixture that I ran previously had the same color.


Is there anything else I can do without removing the rad and backflushing it with a pump? Or should I just go for a few trips and change the water in between to see if it gets better?

Thanks,


Daniel

[Big hammer]

Alot of good information, but what are your symptoms of overheating? Coolant level cold should be under the baffle in the radiator. When I first bought my A I thought it was overheating, I was overfilling the radiator.

[bavArian]

Symptoms of my overheating engine are a fine spray of water through the radiator cap and, if I then keep driving fast, boiling water in the upper hose to the radiator. (probably boiling water in the head)
The spray may have been a slightly undersized quail-gasket. (there was absolutely no resistance when closing the quail)

Cut an addition gasket today and the quail closes with some resistance now which should be fine.



Coolant level cold is relatively low but it seems to find its own level and the thermoquail registers temperature just fine, so I assume that the waterflow coming from the engine is working as it should. Otherwise the quail would show low temperature as the water wouldn't reach the feeler of the quail.


Running water or 50/50 antifreeze didn't make a noticable change.


EDIT: Setting spark to full advance or 3/4 makes no difference, still overheating if I go full throttle for more than maybe a minute.

[Stingray70]

What type of radiator do you have? Some aftermarket units will cause trouble even if they are clean and clear. How is the physical condition of your radiator? Are any of the fins loose from the tubes?

Sent from my SM-G950U using Tapatalk

[bavArian]

Checked the fins some time ago, all seem tight.

The radiator seems quite old, from the pictures I can find via google I'd say it could be an original radiator. If it's a repro it is at the very least 30 years old.
I'll upload a pic of inside and outside tomorrow, maybe someone can identifiy it.

[Stingray70]

Sponsored Links (Register now to hide all advertisements)

Count the rows. Make sure it isn't a two row radiator.

Sent from my SM-G950U using Tapatalk

[1930artdeco]

Sounds like you are losing water and or have a plugged radiator. Mine used to puke out from under the cap and I had a lot of boulders in the upper tank. Or you are pressurizing it from an exhaust crack someplace. Do you have water coming out of the tail pipe?

Mike

[nkaminar]

Something is blocking the coolant flow. My advice is to buy a new radiator from Brass Works and make sure the flow through the engine is not blocked. Drain and save your 50/50 mixture. Remove any thermostat you may have. Fill the system with straight water. Remove the radiator cap. Remove the bottom radiator hose. The coolant should drain out of the radiator and engine within 2 to 3 seconds. You can do the test again by keeping the bottom radiator hose off and blocking both sides with something like a rubber balls. Then fill the system again with water and remove the balls one at a time to check the radiator and engine separately.

[jack backer]

Old radiators in good shape can be saved by removing and back flushing with a hot water pressure washer with degreaser, water pump grease and debris plug the tubes.. you need more heat and chemical than dishwasher tabs and engine temp. I know it’s painful to tear her down but cleaning it correctly will save money. Pulling the cylinder head and cleaning the water jacket finishes the job.

[bavArian]

More Info:


- no thermostat
- coolant level seems to stay constant once it has found its level
- when starting the fine spray of water the mercury is all the way to the top
- no water from the exhaust and no white or blue smoke
- checked the rad, it's a 2 row repro which has a tag 'Eureka' on it



From your answers there seems to be no way around removing the rad and flushing it properly. Then I'll just have to do that after the next car meet mid june.

I'll report back when I have the rad removed.


Also I will take my IR-thermometer with me on the next ride to get proper values from head and radiator.

[1crosscut]

Stick a dial meat thermometer directly into the coolant to get accurate temperature readings. Let us know what you are seeing.
The I.R. units are okay for a general idea of temp but the probe in the coolant is the best way to tell the actual temperature of the coolant.

[Gene F]

The radiator is bad.

When I got my car it was mostly fine, till it got worked hard, or if it was a real hot humid day then it would overheat. Turns out back in the day Sears made cheap radiators with not enough capacity. It could have a blockage, but why bother, just call Snyders and get the best one they sell, and be done with it. Seems like they were $585 last I looked. Do it now before you end up with bigger problems.

[bavArian]

Well, the only one in stock atm is 730 $. For me that's around 1100 $ including shipping. Hence I'll check to see if the current rad can be saved before considering a new one.

[WHN]

Originally Posted by bavArian

Well, the only one in stock atm is 730 $. For me that's around 1100 $ including shipping. Hence I'll check to see if the current rad can be saved before considering a new one.

Spend the money and move on to fixing the next problem.

Enjoy.

[ETAModel]

If you can find an old school radiator shop they can unsolder the top and bottom. Then vat the radiator and dissolve the crap that's blocking it. Then they should rod the radiator and solder the top and bottom on.
Now finding a shop who'll do this is harder these days. The local shop near me told me they'd sell me a new radiator but not vat or rod the old one.
The more I drive the better I get at controlling the temp, so I'm good RN.
I wish you luck.

[shew01]

An old school radiator shop can also swap out a plugged core for a new one, and keep the bottom and top tanks.


Sent from my iPhone using Tapatalk

[katy]

How is the outside of the radiator core? Can you see through it good? Or is it clogged w/several coats of paint? Dead bugs? Mud? Other crud?

[bavArian]

The radiator is clear of any dirt, mud or excess paint. I can clearly see through the fins. It definitely is not an airflow problem. It also has flat tubes, not round ones.
Btw., I have the engine pans installed as well.


I'm suspecting the lower part of the radiator is at least partially coated with grease or dirt, reducing the heat transfer from water to radiator.

I will probably take a look through the outlet when I have it on the workbench, maybe that will show me why the lower part of the radiator stays cool while driving but the water doesn't.

[eagle]

There are a lot of products out there to clean the radiator. I'd try one or two of those first. Radiator shop should be able to point you towards one that is effective enough to do the job.

[Stingray70]

Originally Posted by bavArian

Well, the only one in stock atm is 730 $. For me that's around 1100 $ including shipping. Hence I'll check to see if the current rad can be saved before considering a new one.

I know you dont want to hear this but I dont think that a 2 core radiator will ever work properly. No matter how good it looks. Don't waste time trying to get an inferior product to work.

Sent from my SM-G950U using Tapatalk

[katy]

Possible water pump problem?

[mass A man]

This is an odd problem, but it almost sounds like there's sand in the bottom tank of radiator. You shouldn't have to spend over a thousand dollars to fix this- whatever the problem is. Pull the radiator and do some detective work. A two row core will work fine if you have a clean cooling system and a good water pump. This CAN be fixed.

[GerryAllen]

Just a thought, I cleaned my rad out with vinegar. Drained the water, replaced it Vinegar took the car for a 25 mile run. When I got home I drained and flushed the rad and observed the color. I then did a 2 gallons vinegar and 1 gallon water mixture and did a run in the car, repeated the above procedure. Did a 1 gal vinegar to 2 gallons water and drove the car, after the third run I could not believe what came out when I drained the rad. I don't know how to upload pics or I would show you. It looked like a tub of S--t. If some one will give me their email i will send picture and you can post it,.

[GerryAllen]

Originally Posted by GerryAllen

Just a thought, I cleaned my rad out with vinegar. Drained the water, replaced it Vinegar took the car for a 25 mile run. When I got home I drained and flushed the rad and observed the color. I then did a 2 gallons vinegar and 1 gallon water mixture and did a run in the car, repeated the above procedure. Did a 1 gal vinegar to 2 gallons water and drove the car, after the third run I could not believe what came out when I drained the rad. I don't know how to upload pics or I would show you. It looked like a tub of S--t. If some one will give me their email i will send picture and you can post it,.

Just as info I bought an Infrared Thermometer gauge from Oreilly's that that you point at the rad and it reads the temperature of the rad. I use it often and find the difference between the top of the rad and bottom to be about 30 degrees. Hope the above write up helps someone in the future.
Gerry Allen Birch Bay WA.

[Gene F]

BarAvin, may I recomend trying this before you spend a buch of money either way? 50 / 50 mix of distilled water, and vinegar. Take it for a 18 KM spin of so, and then see where you are.

[nkaminar]

Sponsored Links (Register now to hide all advertisements)

Did you test the flow as detailed in post #8? You can do this in the car. There is nothing like test data to understand a problem.

[1930artdeco]

< Turns out back in the day Sears made cheap radiators with not enough capacity>

I have exact same radiator as a spare and when I asked Alex Janke that s exactly what he told me. Mine even has the Eureka yet on it as well. I got it just for the frame as a spare I case anything happened to the original. It will hurt but my advice is junk the core and put a new 3/4 row in.

Mike

[Gene F]

Originally Posted by 1930artdeco

< Turns out back in the day Sears made cheap radiators with not enough capacity>

I have exact same radiator as a spare and when I asked Alex Janke that s exactly what he told me. Mine even has the Eureka yet on it as well. I got it just for the frame as a spare I case anything happened to the original. It will hurt but my advice is junk the core and put a new 3/4 row in.

Mike

I have one in the attic of my garage too.

[nkaminar]

A usable replacement for the radiator is a 55 gallon barrel. It has about the right heat dissipation. You can weld some brackets to the frame to hold the barrel. Just make sure your front suspension is beefy.

[katy]

Originally Posted by bavArian

I'll upload a pic of inside and outside tomorrow, maybe someone can identifiy it.

Still waitin'

[CT Jack]

Remove the radiator from your car. If you have a radiator repair shop near you that knows how to solder and clean radiators have them remove either the top or bottom cover which we call cans. Then they can flush or brush the inside of each tube to make sure they are open and clean. If any of these tubes are blocked this will cause overheating of the coolant.
Keeping the fins clean is important but keeping the tubes open is the most important.
This will be the least expensive way of fixing your problem.
Viel Gluck

[bavArian]

Originally Posted by katy

Still waitin'

Sorry, didn't have time until now.
Links to the pictures are below. (I attached them to the post as well)
Radiator outside:
https://c.gmx.net/@32955722184943758...S96pb-oVgIoxJg
Radiator inside:
https://c.gmx.net/@32955722184943758...TMO8amCZojO8GQ
Radiator tag:
https://c.gmx.net/@32955722184943758...QMK9wlyZqoV4uw



I did another run today with fresh water and 2 dishwasher tabs inside. Had the radiator boiling today as well but I think not as strong as it was on the last trips. It was warmer today as well.
Flushed the system afterwards, the water was slightly brownish again.

Seems I'll have to try the vinegar but I'm a bit hesitant to do so with the radiator in the vehicle. I think it would be wise to flush engine and radiator separately to avoid getting more dirt in the radiator. Is that correct or am I simply overcautious?
If the weather is good I may remove the rad. on the weekend and check flow rate and the bottom tank.

[1930artdeco]

You can also use a GANO filter that goes in the top hose, it will collect the larger pieces. For the finer stuff use a pair of pantyhose.

Mike

[mfarley]

Can you get this where you are?

https://www.evapo-rust.com/thermocure/

This is a fantastic rust cleaner, specifically designed for an automobile cooling system. Run it in your radiator for a few days or up to a month. It will come out black when you drain it, and if you leave it in the bucket a few days, all the iron and rust sediment will be at the bottom. Just cleaning the rust off the interior of the water jackets and radiator can lower your operating temperature. Please note that this product does not protect against overnight freeze-up if that's the case where you are and your time of season.

Micheal

[1crosscut]

I think it would be helpful for us to know that actual temperature of the coolant when you drive it. Use a thermometer like the one I posted a picture of in post #11.

[bavArian]

Did a test-run today in hot weather, around 82 °F ambient temp. and dry.
Didn't need to measure the coolant temperature as I could easily hear the water boiling after a few miles. Opening the radiator cap resulted in a small cloud of steam and a bit of water loss through the radiator cap again, roughly half a minute later the water stopped boiling but obviously was still very hot. With the hot weather today it was almost impossible to drive the car without overheating.

Measured the head after I came home (needed a few minutes to find the laser thermometer) and got 97 °C / 207 °F at front and back. I'll take the thermometer with me next time, but I would say that the head has at least 100 °C / 212 °F while driving.

The oil pan was cooler, around 67 °C / 152 °F.


The difference between top and bottom of the radiator when running the engine is only around 5 to 10 °C / 9 to 18 °F. That seems to be not enough to cool the engine properly.

After letting the car cool a bit I took off the radiator shroud, disconnected the hoses and did a drain test. Completely filled up the water drains very fast for around 2 seconds and then the drain considerably lessens. That takes another 2 or 3 seconds until it only trickles. So I guess there really are a few pipes that don't have proper flow? Should the radiator really be completely empty within 2 to 3 seconds or is a drop in flow normal as the water column inside the radiator decreases?


I've blocked off the lower hose now and put 50/50 water/vinegar in the radiator. I'll let it soak until tomorrow and then do another drain test. If the result is no different I'll remove the radiator and try to backflush it with a pressure washer or a high volume water pump.




EDIT: Measured it just now, it's a ~5 fin / inch radiator. Does someone know with how much fins / inch and tubes the original radiator was designed? If it was 5 / 2 as well it should be able to cool enough if everything works as intended.

If the originals were 8 / 2 or 5 / 3 then it will probably never be able to handle the heat.

[1crosscut]

In your first post you wrote that the timing was spot on and was checked with a timing light. However problems like this are often caused by the timing being off. How about giving it a go setting the timing without the timing light?

[WHN]

The bottom of your radiator should be cooler than the top, that’s how they work. Model A’s have a syphon cooling system aided by a water pump. The syphon by far does most of the work. Hot out the top into the radiator, cooler back into the engine at the bottom of your radiator.

My question would be how hot is the water at the top and how hot is the water going back into the engine at the bottom? Is the engine over heating? What’s the temperature of your engine back by cylinders 3 and 4.

This is a really simple system. It will work just fine even without your pump.

Simple! Hot coolant exits engine at the top and into radiator. Using syphon, coolant flows down radiator and out the bottom back into the engine. If that is not what is happening? Something is plugged. If engine is not over heating while running now. Than you have sufficient cooling flow. Might still have some clogged radiator tubes but the rest of system is working properly.

Have you ever had to call a plumber to snake out a clogged or slow moving pipe? No pump is moving the waste water, gravity (like syphon). Moving slowly, water/coolant backs up.

Remover lower hose and pour water into the top of your radiator. How fast is it coming out. That will tell you the story of your radiator.

Can’t go wrong with new!

Enjoy.

[WHN]

The bottom of your radiator should be cooler than the top, that’s how they work. Model A’s have a syphon cooling system aided by a water pump. The syphon by far does most of the work. Hot out the top into the radiator, cooler back into the engine at the bottom of your radiator.

My question would be how hot is the water at the top and how hot is the water going back into the engine at the bottom? Is the engine over heating? What’s the temperature of your engine back by cylinders 3 and 4.

This is a really simple system. It will work just fine even without your pump.

Simple! Hot coolant exits engine at the top and into radiator. Using syphon, coolant flows down radiator and out the bottom back into the engine. If that is not what is happening? Something is plugged. If engine is not over heating while running now. Than you have sufficient cooling flow. Might still have some clogged radiator tubes but the rest of system is working properly.

Have you ever had to call a plumber to snake out a clogged or slow moving pipe? No pump is moving the waste water, gravity (like syphon). Moving slowly, water/coolant backs up.

Remover lower hose and pour water into the top of your radiator. How fast is it coming out. That will tell you the story of your radiator.

Can’t go wrong with new!

Enjoy.

[bavArian]

Originally Posted by 1crosscut

In your first post you wrote that the timing was spot on and was checked with a timing light. However problems like this are often caused by the timing being off. How about giving it a go setting the timing without the timing light?

I did set the timing without a timing light. Went by Les' method in the red book.

To test the timing after encountering the overheating-problem, I marked TDC on the crank pulley and the engine and used a flasher pistol hooked up to cyl. 1 to check the timing. I sincerely doubt that it's off by more than 1 degree because the two marks were right next to each other when I let the starter turn the engine with the timing lever all the way up. That obviously didn't change when I started the engine and let it idle. Also confirmed that the advance works properly because the timing marking went towards the passenger side when advancing with the lever.

Originally Posted by WHN

My question would be how hot is the water at the top and how hot is the water going back into the engine at the bottom? Is the engine over heating? What’s the temperature of your engine back by cylinders 3 and 4.

As written above, the water was definitely boiling. At slow idle after stopping as well as the first 30 or so seconds after shutting the engine off.

Head-temperature was at 100 °C / 212 °F, the enthalpy of evaporation keeps it there as long as enough water is in the head. (measured ~97 °C after it stopped boiling)


An older post here on fordbarn says that there should be 20 to 30 °F difference between inlet and outlet of the radiator. That seems to not be the case with my radiator, I'm closer to 9 - 18 °F.

Also I checked the radiator from the top today with a lamp again and noticed two of the visible tubes at least partially clogged with what looks like rust / dirt. Therefore I assume that other tubes are clogged as well. Maybe it's old rust / dirt from engine or rad. that was loosened up enough to make it's way through the engine to the top of the radiator.


So I'll remove the rad. tomorrow, backflush it and then check the drain behaviour again.




Apart from all that, can someone tell me if the original radiator of the normal A's had 2 tubes and 5 fins per inch? Or did they have less / more tubes or fins?

[31Tudor]

Original radiator depending on manufacturer:
Ford - 4 rows, 94 tubes
Flintlock - 4 rows, 109 tubes
McCord - 5 rows, 87 tubes

Then I counted about 7 fins per inch on my original 1928 radiator.

[31Tudor]

Original radiator depending on manufacturer:
Ford - 4 rows, 94 tubes
Flintlock - 4 rows, 109 tubes
McCord - 5 rows, 87 tubes

Then I counted about 7 fins per inch on my original 1928 radiator.

[bavArian]

Huh, they were round tubes I guess? Anyone have any idea how round vs. "elongated" (not sure about the name of the new ones) tubes behave regarding cooling capacity?

[31Tudor]

28-29 original radiators all had round tubes
30-31 original radiators were elongated or kind of oval - they had 102 tubes

[31Tudor]

28-29 original radiators all had round tubes
30-31 original radiators were elongated or kind of oval - they had 102 tubes

[Karl Wescott]

Sponsored Links (Register now to hide all advertisements)

Another thing to check is the impeller of the water pump. The flathead V8 guys often have an issue where at high speed/hot water the pump will cavatate and not move water, while moving water fine at low engine speed. To check this issue you would need to make sure the volume of water continues to increase from idle to full throttle.

[Karl Wescott]

A high tech thought to check the radiator itself is with a thermal imaging camera. This should be able to show gradual cooling (radiator fine, just not moving coolant) or an abrupt temperature change (showing a block in the radiator). These are expensive but you might be able to get the local Fire Brigade to show off their "cool" toys, while you show off your "hot" one.

[bavArian]

Update:

Took apart the entire cooling system today to backflush radiator and engine several times. Used 50/50 vinegar/water on the radiator and diluted amidosulfuric acid for the engine. Got a bit of rust and dirt out of engine and radiator but not much.
At least the radiator seems to drain faster now.


Took a look at the water pump as well. The impreller was a little rusty (not much) but there was no sign of cavitation marks on the 3 blade impreller. I doubt that's the / a problem.


While the fan belt was off I blocked off the water inlet of the engine and filled it up to the outlet. There are no bubbles coming from the engine when spinning up the engine hard or letting it run fast. So the head gasket seems to be fine.


What I did notice today was that the cylinder head warms up unevenly. The drivers side with the pistons warmed up moderately to around 50 °C / 122 °F while testing whereas the intake/manifold side was already at 85 °C / 185 °F. Coolant temp. was at ~ 53 °C / 127 °F.
Is that a normal behaviour?


I will definitely check that on the next test drive. What would be the reason for the manifold side to get much warmer than the rest of the engine? Blocked water passage?

[1crosscut]

I've always found the the passenger side #1 cylinder area is the quickest to warm and the heat generally soaks through the head from that point back to the rear.

[bavArian]

Took it for a short test drive again today. It was ~4 °C/ 7 °F colder today but I think the heat dissipation radiator to ambient is a little better. Still not good enough mind you, but I was able to drive continuously (@ ~ 40mph) without a boiling radiator and the temps actually went down when driving downhill.
I also found that one side of the radiator was considerably cooler right after stopping than the rest. After half a minute or so the entire rad. had a constant temperature, with a difference of about 6°C / 11 °F between top and bottom. So there's obviously still a few clogged tubes. I'll check with a local radiator shop how much removing and refitting both tanks would cost me. If it's reasonable I'll rod it out myself, if not I'll probably have to bite the bullet and order a new radiator.


Head-temperature was more even when driving, under 10 °F difference between cylinder and manifold side.


Question: Which temperature should the water have when entering the block?

I'm measuring ~ 80 °C / 176 °F at the lower tank leaving the radiator.

I assume that's around 15°C / 30 °F too hot?

[WHN]

Originally Posted by bavArian

Took it for a short test drive again today. It was ~4 °C/ 7 °F colder today but I think the heat dissipation radiator to ambient is a little better. Still not good enough mind you, but I was able to drive continuously (@ ~ 40mph) without a boiling radiator and the temps actually went down when driving downhill.
I also found that one side of the radiator was considerably cooler right after stopping than the rest. After half a minute or so the entire rad. had a constant temperature, with a difference of about 6°C / 11 °F between top and bottom. So there's obviously still a few clogged tubes. I'll check with a local radiator shop how much removing and refitting both tanks would cost me. If it's reasonable I'll rod it out myself, if not I'll probably have to bite the bullet and order a new radiator.


Head-temperature was more even when driving, under 10 °F difference between cylinder and manifold side.


Question: Which temperature should the water have when entering the block?

I'm measuring ~ 80 °C / 176 °F at the lower tank leaving the radiator.

I assume that's around 15°C / 30 °F too hot?

To hot.

Get a new radiator. If you are planning on driving the car. You need a good cooling system. Somethings need to be right. This is one of them.

[nkaminar]

I think you should "bite the bullet" as you say. I don't know about where you are but here lots of Model A parts are listed on Craigslist.org. You may be able to find a good used radiator locally. Just make sure it has lots of tubes, is clean inside, and has lots of fins. Compare with what you have. Or order new from Brass Works or Snyders or another vendor.

[bavArian]

Haven't seen a "good" radiator here in Germany for the A. The only available ones are the cheap aluminum rads, but they seem to have fitment problems and they look abysmal to be honest.
You can also get used ones, but chances are that they have the same problem as my current one, so that's out of the question as well.

[katy]

It sounds like there may be something blocking part of the top of the core, possibly a loose baffle, possibly some foreign material?

[Gene F]

Do you think you are gaining any ground? Your comment about draining faster.... there is a driveway test as to how long a radiator should drain, but I don't recall it. Perhaps someone will chime in, with how many gallons/litres it holds too.

[bavArian]

Originally Posted by katy

It sounds like there may be something blocking part of the top of the core, possibly a loose baffle, possibly some foreign material?

Hmm, I can't hear anything loose inside the rad. Tilted and shaked it enough in the cleaning process.
Anyway I'll take a borescope and check the tanks as soon as I have time to do so.

Originally Posted by Gene F

Do you think you are gaining any ground? Your comment about draining faster.... there is a driveway test as to how long a radiator should drain, but I don't recall it.

The radiator does drain a bit faster after the cleaning, it takes around 3 to 4 seconds I would say for it to just trickle out of the outlet. Also I think the cooling was improved, it's just not good enough for hot weather.

[CT Jack]

Based on what you are reporting it sounds you definitely have a plugged radiator. I submitted a post #31 that suggests you remove the radiator and have a radiator repair mechanic clean it. If you have the correct radiator and the metal (brass) is in good condition they can unsolder one of the covers and brush the inside of each tube. This will clear out any blockage and also improve heat transfer. Do not allow them to pressurize the radiator it is not designed to be pressurized and will cause damage.

[nkaminar]

Here is another idea. There is a thing called "Water Wetter" that is supposed to lower the coolant temperature. You could try running that and just water, no antifreeze. Drain it out and save it during the winter where you will need the antifreeze.

Many year ago, before my time, when only water was used, people would drain their radiators while they were at work in the winter so the block would not freeze. They would have to pour the water back in before they could drive home. Not sure how they kept the water from freezing, maybe they wrapped the container in a blanket.

By the way, the radiator should drain in 2 to 3 seconds. 3 to 4 is not bad and may just indicate that there are a reduced number of tubes. Or may indicate that some tubes are blocked, as Jack said.

https://www.amazon.com/Red-Line-8020...ews/B000CPI5ZK