Temporary Radiator Suggestions? (1 Viewer)

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First i've heard of this maybe it's dependent on what county you're in

I clear codes pulling into the smog station and they just run it and i'm out.
Sorry, poorly phrased. "I" clear the codes and run it around to warm things up, "they" run it on rollers and check under the hood for maybe half an hour. If I don't run it for a while, CEL's show up real fast.
 
However, it will remain in the cooling system longer because it will not be pressurized and blow it out.

But boiled water (gas) is ineffective at removing heat from the cylinders. You have water, but it's not cooling.
 
But boiled water (gas) is ineffective at removing heat from the cylinders. You have water, but it's not cooling.
Well, tell that to all the old car guys that have had to do it to limp home.

BTDT.

If you allow it to pressurize, it WILL blow out the liquid.

If you don't, and the engine is not being worked hard and going over 212°F, then it will not boil out and turn it all to gas / steam vapor in the time it takes to get there. If he was driving for HOURS, I would maybe think differently. He's driving maybe 15 minutes at a time.

Let's assume for a moment that he has a hose with a hole in it down low on the engine.

If the cap was on, it would pressurize, expanding the hose and push out the coolant.
If the cap was off and it wouldn't allow it to pressurize, you will lose SOME coolant, but not all of it, and the hose will not leak because it's not being pushed open.

Just like all the old cars did not have a coolant recovery system on them, the capacity was oversized so there was always some "air gap" in the radiator because as it warmed up, the system would push out and "excess" coolant, then it would stabilize because it would not expand any further. Just like this will do. The coolant (water) will expand some and will allow some (maybe a quart) to overflow out of the radiator, but it will not PUSH it out unless he has a massive head gasket leak where the cylinder it truly pressurizing the system. Then it will violently puke coolant out of the radiator. Clearly he does not have it that bad yet, but he's still trying.
 
I can say from experience the cooling system will work surprisingly well without being pressurized.

You will run into an issue where coolant in the head will boil after the vehicle is shutdown and circulation stops. Not ideal.
 
But boiled water (gas) is ineffective at removing heat from the cylinders. You have water, but it's not cooling.
Well said.
What people don't know is what's going on at the cylinder walls. You have a thermal layer along the cylinder walls acting as an insulator. The lower the pressure the less heat transfer, higher, better. Most of the time you don't know your block and head are running hotter because everyone watch's water temp not metal temp.
There's a company out there selling waterless coolant. They claim lower temps. If one looks at the independent studies done, you find extreme metal temps because the coolant doesn't absorb heat as well as water. But, everyone loves it because they see lower coolant temp. Same here without a cap. Its all physics.

I say, go for it, it will either work or not

EDIT: and yes I have driven home with a loose cap.
 
Well said.
What people don't know is what's going on at the cylinder walls. You have a thermal layer along the cylinder walls acting as an insulator. The lower the pressure the less heat transfer, higher, better. Most of the time you don't know your block and head are running hotter because everyone watch's water temp not metal temp.
There's a company out there selling waterless coolant. They claim lower temps. If one looks at the independent studies done, you find extreme metal temps because the coolant doesn't absorb heat as well as water. But, everyone loves it because they see lower coolant temp. Same here without a cap. Its all physics.

I say, go for it, it will either work or not

EDIT: and yes I have driven home with a loose cap.
No personal experience, but if you're talking about the stuff Leno likes, I've been told it also wipes out water pumps on modern cars.
 
I couldn’t bare to read this entire thread so I’ll just ask. Will an engine with a leaking HG pass emissions testing? Why not just register it as Non-op (which it really is) so you have time to correct the problems?
 
With no radiator cap, your coolant will boil at a lower temperature
Yes
and be ineffective at cooling.
No, it will be effective up to the boiling point of water at atmospheric pressure, which generally is sufficient

It's not ideal, and agree best course of action is to fix the root cause of the issue.

Can tell you from first hand experience, running an open system temporarily works IF your cooling system isn't running at the ragged edge.

Something to keep in your bag of tricks if you find yourself with a slow leak out in the bush. Removing the radiator cap to slow the leak may just let you limp home rather than be stuck it boonies
 
I couldn’t bare to read this entire thread so I’ll just ask. Will an engine with a leaking HG pass emissions testing? Why not just register it as Non-op (which it really is) so you have time to correct the problems?
Asked before, told it should. Fingers crossed. If I had another vehicle I'd just park it and start taking the head off.
 
Another little point. For every pound of pressure in the cooling system, the boiling point goes up 3°. So having it all tight and leak free is important.
 
No personal experience, but if you're talking about the stuff Leno likes, I've been told it also wipes out water pumps on modern cars.
Yep
You should see the testing on that. They actually came down to my work and did a seminar. I didn't say anything but some of the other instructor's gave the guy a hard time.

Its actually straight Glycol with an additive. Glycol absorbs heat poorly which is why the water temps are low but the metal temps are high. The nice thing is little to no acid build up.
 
Another little point. For every pound of pressure in the cooling system, the boiling point goes up 3°. So having it all tight and leak free is important.

Unless it's leaking.

Then keeping the water in it while it's being driven is more important than raising the ceiling on the boiling point higher than what is necessary
 
So, I've been in your shoes.
Had a leaking radiator in my hzj105 at a time when I was flat broke. I ran it for months with no radiator cap, and filling with water before every trip to/from work.
With cap in, it would lose water fast, with no cap in, if I forgot to top up the water, I'd get a second trip with some margin for error
This is commonly done on bush taxis in rural Africa, as in the example below. They keep engines with trashed cooling systems running for many many kms.

 
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This is commonly done on bush taxis in rural Africa, as in the example below. They keep engines with trashed cooling systems running for many many kms.


Am I missing the point ?
 
I was just saying there's precedent for running a cooling system unpressurized, as in the vid I posted. It's often done in places where they lack the resources for major repairs and parts-sourcing, etc.
Just because they do it in third world countries to total beater rig doesn’t make it right especially if you’re trying to preserve your Land Cruiser.
Point taken though.
 
Fix that head gasket before you get coolant or water in the oil. If your driving it with coolant in the oil than you can say goodbye to your bearings.
 
Fix that head gasket before you get coolant or water in the oil. If your driving it with coolant in the oil than you can say goodbye to your bearings.
^^^
This
 
That head is going to be taco shaped by the time you bother to correct the HG. This entire thread is proof you can lead a horse to water but can't force it to drink. I cannot for the life of me figure out the mental gymnastics it would take to think overheating an engine repeatedly is better than risking a radiator. I still don't understand how you even came to the conclusion that a blown head gasket will kill a rad. What color is the sky where you live?
 

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