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I started it and waited roughly 2 minutes and it started overflowing again. Stuck my finger in the Coolant and it wasn’t hot. I didn’t include any information about the gauges because I am not certain they work. If we are assuming they work then the gauge reads cold when the coolant comes out.
Well, I guess that your findings make my point. Of course, I am not there to completely analyze your issue, but if the coolant is not warm/hot, the thermostat has not opened and there is no flow. Could the thermostat be stuck open? Sure. Personally, I would start the car from cold and watch and wait. Wait for the thermostat to open. The surging of the coolant tells me that the cooling system is working to purge air as it should and when the thermostat opens, if then working properly, you will almost instantly get warm/hot coolant flowing through the system. BTW, this will take longer than your two minutes starting from cold. Do you happen to know what degree thermostat is installed?
 

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If the video was when the car was cold (and I suspect it was) then it is overfilled. The cold level should be about a 1/4 inch above the header plate. This gives it enough room to expand as the coolant heats up.
Also if a thermostat is either stuck open or closed your engine will overheat. The purpose of the thermostat is to keep the coolant in the radiator so it can cool. The thermostat will open and close to regulate the engine temp. You always have coolant circulation in the engine via the waterpump and thermostat bypass.
 

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If the video was when the car was cold (and I suspect it was) then it is overfilled. The cold level should be about a 1/4 inch above the header plate. This gives it enough room to expand as the coolant heats up.
Also if a thermostat is either stuck open or closed your engine will overheat. The purpose of the thermostat is to keep the coolant in the radiator so it can cool. The thermostat will open and close to regulate the engine temp. You always have coolant circulation in the engine via the waterpump and thermostat bypass.
I agree with most of what you have had to say. However, I have never seen a thermostat that is stuck open cause a car to over heat. Thermostats play an important part in the cooling system, however, many that don't understand that have removed thermostats from their systems altogether. Also, the thermostat bypass indeed allows for some circulation, but not nearly enough to cool correctly. What it does do is help purge the system of air and coolant pockets that could lead to cooling system issues.
 

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I agree with most of what you have had to say. However, I have never seen a thermostat that is stuck open cause a car to over heat. Thermostats play an important part in the cooling system, however, many that don't understand that have removed thermostats from their systems altogether. Also, the thermostat bypass indeed allows for some circulation, but not nearly enough to cool correctly. What it does do is help purge the system of air and coolant pockets that could lead to cooling system issues.
Correct and yet SO many people think the opposite.

It won't overheat, but it will also not heat up to temp as fast as it should.
 

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I have seen overheating with a thermostat removed (worked in a rad shop many years ago) but you are correct heating up the engine will take longer.
The reason it can overheat is removing the thermostat probably triples the flow rate of the coolant this causes the coolant to move through the radiator faster than it can be cooled.
 

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"Is it possible the thermostat was installed backwards?"

This was my symptoms too, right after first start after a bunch of maintenance (including adding a thermostat since one was not installed when i got the car...).

I put the thermostat in correctly - and no more issues...
 

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If what U said, he'd be complaining of an over heating problem instead! 🤔
Right, no flow, the engine would overhear/boil over.
He didn't say it was boiling over, so he probably has a simple case of an over filled radiator, hence why I mentioned installing an over-flo catch can.
He wrote back and said he likes the engine compartment the way it is & didn't want to
 

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Correct and yet SO many people think the opposite.

It won't overheat, but it will also not heat up to temp as fast as it should.
An internal combustion engine can be considered as a heat pump. They tend to have a "sweet spot" operating temperature, which optimizes performance. This sweet spot is engineered in when the engine is designed. With automobile engines the chosen thermostat is typically in the 180 to 195 degree range. It basically works when the engine is cold, allowing the coolant in the block to get to the opening temperature pre-set of the thermostat, then the thermostat opens allowing free flow of all the coolant in the entire system. It does not control overhearing, that is left to the radiator, and/or other cooling devices. 🙂4
 

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Right, no flow, the engine would overhear/boil over.
He didn't say it was boiling over, so he probably has a simple case of an over filled radiator, hence why I mentioned installing an over-flo catch can.
He wrote back and said he likes the engine compartment the way it is & didn't want to
....install an over flow catch system.
So he's stuck watching the coolant level in his radiator and maybe an occasional loss of coolant if he over fills it. 🙂
 
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