Coolant overflow capacity?

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clementine

clementine

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How many ounces are necessary for coolant expansion tank?

What are you running for your coolant recovery?

What does the stock setup for a 67/8/9 383 barracuda look like? (I have asked google with surprisingly poor results so apologies)

383 with a heater and 24.5” tank.

I drained the system and flushed. Then put in 3 gallons. In some of my research, I ran across the figure of allowing 12% of capacity.

3 x 128 x 0.12 = 46 ounces…. And that might be low on actual capacity of the entire system. Do I really need that much?
 
clementine said:
How many ounces are necessary for coolant expansion tank
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2-3 cups


clementine said:
What are you running for your coolant recovery
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Not using coolant recovery. Using the top of the tank like the OEM designed it.


clementine said:
What does the stock setup for a 67/8/9 383 barracuda look like? (I have asked google with surprisingly poor results so apologies
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67-69 A body don't use a recovery system. You leave an air gap at the top of the tank about an inch.

If the coolant expands enough to puke some out, when it cools off it pulls in a little more air for the air gap at the top of the tank
clementine said:
383 with a heater and 24.5” tank.

I drained the system and flushed. Then put in 3 gallons. In some of my research, I ran across the figure of allowing 12% of capacity.

3 x 128 x 0.12 = 46 ounces…. And that might be low on actual capacity of the entire system. Do I really need that much?
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Not sure what you are trying to convey here
 
Coolant recovery tanks didn't show up on Mopars till 71-72 Before that just a puke tube to the ground.
Some aftermarket tanks are about 2 quarts. Some are clear others are different colors that can be had from Summit/Jegs
You may be able to use a tank/bottle from a 73 up Dart or Duster.
In the photo is a black expansion tank from Summit. Lower right corner

IMG_0009.JPG
 
Dana67Dart said:
Not sure what you are trying to convey here
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That’s the math for figuring out how much “they” recommend for coolant overflow capacity. I’m not sure who they are… but they are out there.

I am having trouble with my communication skills lately so no big surprise I have failed. BUT…. I have an answer and am closer to the truth.

Probably don’t need one.

Thank you FABO!
 
The aftermarket bottles seem to be a quart. But only get about 1/2 full.

My dad added a overflow to my 67 dart. He used a 1qt orange juice bottle.

If you do decide to use one be sure it is vented. Otherwise it is like having a rad cap that is stuck closed.
 
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In our older cars, the coolant recovery tank is the top radiator tank. You only fill the radiator to about 1.5" - 2" from the top. Enough to cover the flues, plus "a little more". The left over space IS the recovery tank. With no additional tank, you must not fill slap to the top. There has to be room for expansion.
 
More information that I should have put in earlier (guilty look). Not a stock deal.

Maybe I’ll slide an aftermarket on the side (vented)

image.jpg


image.jpg
 
There's also a difference between a "coolant recovery" tank and an "expansion" tank. Lemmie splain, Lucy. A coolant recovery tank is simply that. A tank that catches overflow from the radiator. An expansion tank is actually part of the pressurized radiator and must be located higher than the radiator's top tank. These are normally used on vehicles that mount the radiator way down low and have no cap on the radiator. The radiator fill cap in on the expansion tank. Ford used expansion tank early on in the late 50s and through the 60s. Now almost all new cars have them. Lastly, there's a "puke tank". The puke tank is just that. A small tank that only gets what the radiator discharges. The difference between it and a "real" recovery tank is, the recovery tank has a tube that runs down to the bottom from the cap. That tube is where the coolant comes in from the radiator, but it also is where the excess coolant in the overflow tank is sucked back into the radiator when it cools back down. I've never seen any style of recovery tank that worked very well.
 
RustyRatRod said:
I've never seen any style of recovery tank that worked very well
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I have been eyeing the recovery tanks that have the inlet on the bottom and a hole in the cap. I’m assuming that style would require the cap to be as high as the rad cap?

I check fluids before the first start of the day so it’s no biggie but in attempt to not spill coolant when I don’t have to…meh, maybe saint Petey will be impressed
 
clementine said:
I have been eyeing the recovery tanks that have the inlet on the bottom and a hole in the cap. I’m assuming that style would require the cap to be as high as the rad cap?

I check fluids before the first start of the day so it’s no biggie but in attempt to not spill coolant when I don’t have to…meh, maybe saint Petey will be impressed
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I don't know. I'm not a fluid dynamics expert. How full is your radiator?
 
Question...


clementine said:
I check fluids before the first start of the day so it’s no biggie but in attempt to not spill coolant
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Why are you checking the coolant every time you drive your car?

Racing?


You can still keep an inch of air at the top of the radiator (regardless of if it is new or old, aluminum or copper brass)
 
Dana67Dart said:
Question...




Why are you checking the coolant every time you drive your car?

Racing?


You can still keep an inch of air at the top of the radiator (regardless of if it is new or old, aluminum or copper brass)
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The barracuda just got a new rad and water pump install.... so coolant check
Then I had to drain and trim the lower hose and refill....so coolant check
The duster needs rad and heater core...so coolant check....

Its just kind of been a theme lately :rofl:

Being a newer build (the barracuda) and Im still doing shakedown runs, I check the easy stuff before closing the hood for a rip.....

The hydraulic TO bearing res is easy cause its white plastic. Basically a brand new car....but built by "just a guy."
 
clementine said:
I think she has fluid an inch down. Im still getting a little dribble out of the barb so I thought I'd catch it.

Still learnin.
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I would drop the level until the tops of the flues JUST are uncovered and see how much room you have. Some radiators have more than others. I'd fill it up maybe 1/2" to 1" above the flues and call it full. I bet it's either too full, or your cap is bad, or both. I'd throw that cap in the garbage anyway. It's import junk. You should be able to run a 13 pound cap with no issues. That one is almost 16. The less pressure, the less stress on everything.
 
I used an NHRA Approved 12OZ Strohs can for 8 years with no issue. We are talking the old Gold and Silver Variety! They did not make me upgrade
to the Blue and Gold Variety when it superseded the previous! Alex got a break there! In other words they were not all to picky as long as you have a vessel to catch
the liquid overflow!
 
I never had any overflow so it was no issue! but the requirement was there!
 
1969383S said:
I used an NHRA Approved 12OZ Strohs can for 8 years with no issue. We are talking the old Gold and Silver Variety! They did not make me upgrade
to the Blue and Gold Variety when it superseded the previous! Alex got a break there! In other words they were not all to picky as long as you have a vessel to catch
the liquid overflow!
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I got by with an old STEEL Budweiser can for several seasons on my old Nova back in high school daze. They didn't care what you had as long as you had "something".
 
RustyRatRod said:
I got by with an old STEEL Budweiser can for several seasons on my old Nova back in high school daze. They didn't care what you had as long as you had "something".
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Rob,

As long as you had Anything to catch any potential overflow it met the IHRA/NHRA intentions to keep coolant off the tracks and preserve racing integrity! Crude rule that worked ok!
 
Real world experience-

My 73 318 Satellite did not come with an overflow/recovery tank despite coming with AC.
(It's also got a fixed fan, which is odd to me)

If I run the AC, it will get hot enough to purge some coolant, and after a few drives, the coolant level will be too low.

I added a 1 quart heavy plastic travel cup but found it would over flow when hot, and eventually leave the coolant level too low.

I found increasing to a 48 OZ container solved the issue.

Be sure the hose from the overflow goes almost all the way to the bottom of your recovery tank (effectively creating a "closed system" if kept below the water line in the tank), and that the radiator cap is a "two way" vent.
 
So from what I have read in this situation …
IF I add a catch,

If I get/make one with a vent(hole in the lid) put it as high as the rad cap.

OR just run coolant an inch down.

AND .. run a rad cap that is fewer PSI to lower the pressure on the system to not over pressurize the heater core and other possible leak points.
 
My recovery tank is about 6 inches below the radiator neck.

Works fine.

Instead of opening the radiator to check the water level before every drive, I simply glance at the translucent home made recovery tank, and if the water level is appropriate (I like to keep it somewhere near half full, or a little lower), I'm good to go.

I'd run the correct pressure cap as called for.
 
A vented overflow tank can be as low as you want but the end of the hose from the radiator cap (or if the tank has a hole in the bottom) should be covered with coolant so it will siphon back into the radiator after it cools down (must also have the rubber seal in the radiator cap for that to work well). Completely filling the radiator and using an overflow or expansion tank also adds coolant to the total system volume.
 
I run two of these. The silver one is about 24 oz on the slant and came from Champion with the radiator. The other is on the wagon with a 318, it holds about a quart and came from Amazon. I filled up each radiator to just over the inner ribs, then drove them. There was a couple of inches in the tank when parked, and less once the system cooled off to suck the excess back into the system. I only added these as my local track requires something to catch overflow and while I'm not a racer I did want to take a few runs once in a while.

20160909_200746.jpg


20230624_200850.jpg
 
YY1 said:
If I run the AC, it will get hot enough to purge some coolant, and after a few drives, the coolant level will be too low
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Define too low?

If it covered the core by 1/2 to 1" it was fine.

The radiator will find its equilibrium point in short order.

Fill the rad up to the top.

Drive in hot weather, and the coolant will expand and some will be dumped out.



When it cools the rad will not be full to the top. DO NOT ADD COOLANT

If you keep doing this eventually the coolant will be at a point where no matter how hot it gets no more will be dumped.

If for some reason you keep dumping fluid after a week without refilling then you have some other things wrong like a leaking head gasket.



As to pressure cap...
Screenshot_20240901-205541.png


You decide how much overhead you need
 
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