Operating Temperature - what is the range?

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Drobnock
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Operating Temperature - what is the range?

Post by Drobnock » Tue May 13, 2025 2:51 pm

The discussion on the use of coolant - what is the proper range for the Model T?

And how hot is too hot?


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Re: Operating Temperature - what is the range?

Post by TXGOAT2 » Tue May 13, 2025 3:13 pm

They usually run from about 180 to 200 F. Boiling over is too hot. With modern oil and modern coolant, 200 to 215 F is no problem for the engine, as long as the system is full of coolant and working properly. Any atmospheric cooling system will boil at lower temperatures at higher altitudes.


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Re: Operating Temperature - what is the range?

Post by Norman Kling » Tue May 13, 2025 4:29 pm

As long as it does not start steaming while driving is OK. On a hot day driving uphill, it should not steam, but if you stop and park, it might gurgle a bit. Always check coolant level before driving. It can get low from expansion, or from a leak. Normal level when cool would be about half way up the top tank. If you fill till it is to the top of the neck, it will expand and run out.
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Re: Operating Temperature - what is the range?

Post by JohnM » Tue May 13, 2025 8:31 pm

I run 50/50 antifreeze and have a Bergs radiator. The previous owner had installed a temp sensor on the side of the head. It runs 160 to 180 degrees. On hot days waiting for the light to turn green, it can creep up over190. Once I'm moving it's fine. As Pat and Norman said, if it's not boiling while cruising on level roads, you're fine.


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Re: Operating Temperature - what is the range?

Post by zukote1991 » Wed May 14, 2025 12:14 pm

Good question. For most Model T's running a stock setup, operating temps tend to stay in the 160–180°F range with water or 50/50 coolant. Over 200°F isn’t necessarily a crisis, but if you’re creeping past 212°F regularly, especially under light load, it’s worth checking for a clogged radiator, timing issues, or poor circulation. These engines don’t have water pumps (unless added aftermarket), so thermosiphon efficiency is key.
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Re: Operating Temperature - what is the range?

Post by Scott_Conger » Wed May 14, 2025 12:49 pm

zukote1991 has joined dozens and dozens of chat rooms in the last week...

what a busy busy little bot you are!
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Re: Operating Temperature - what is the range?

Post by Henry K. Lee » Wed May 14, 2025 2:11 pm

And the AI Bot will learn from the not so enlighten souls of age and their lack of technology. After they learn they come and take their spoils of war without firing a shot.

They will take from bank accounts, falsify legal documents, ie, titles and the likes there of.

Shut down the site to NON MEMBERS!


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Re: Operating Temperature - what is the range?

Post by Dan Hatch » Wed May 14, 2025 2:33 pm

Amen brother Hank!!! Shut it down!!!!!


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Re: Operating Temperature - what is the range?

Post by Drobnock » Thu May 15, 2025 12:52 pm

To ask this question again - " what is the proper range for the Model T? And how hot is too hot?"

There is push back on using 100% ethylene glycol (green) for cooling. That is - operating a T Motor at sea level and at 70 degrees F. - 21 C.. What is the safe temperature a motor should operate if the boiling point of the coolant is above 180/200 degree F. range.

If the 100% mix keeps the engine in the 180/200 degree range will there be harm to the motor?

The boiling point of pure ethylene glycol is approximately 197°C (387°F). When ethylene glycol is mixed with water, especially in antifreeze solutions, the boiling point is raised, and the freezing point is lowered. For example, a 50/50 mixture of ethylene glycol and water raises the boiling point to 223°F (106°C) and lowers the freezing point to -35°F (-37°C). (Thanks AI)

The boiling point of distilled water, which is pure water, is 100 degrees Celsius (212 degrees Fahrenheit) at standard atmospheric pressure, which is equivalent to sea level. ( Again AI)

A 50/50 mix of water and ethylene glycol has a boiling point of 223°F (106°C). This is a significant increase from the boiling point of pure water, which is 212°F (100°C). (AI Again)


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Re: Operating Temperature - what is the range?

Post by JohnM » Thu May 15, 2025 5:06 pm

The push back on pure antifreeze is, (as you stated) lowers the boiling point. The T cooling system is not pressureized. Running 180 to slightly over 200 is fine as long as it's NOT BOILING. Most T's will occasionally spit out some coolant after a long hill climb. To put it plainly, cruising on a hot day and it's not boiling but for a gurgle or two from a hill climb or when you first shut it off, you are fine. You don't need to know the precise temperature. You just need to know it is not continually boiling.

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Re: Operating Temperature - what is the range?

Post by TRDxB2 » Thu May 15, 2025 6:43 pm

100% antifreeze is counter productive
Choose by your winter freeze
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freexz coolant.png
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Pick your boiling point based on altitude
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boiling.png
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For Boiling point in an unpressurized system
At sea level a 50% solution raised the boiling point 14°F. At 4000ft the boiling point is 205°F so raising it 14°F would need just a 33% solution.
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boil it 2.png
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So at higher altitudes, where air pressure is lower, the boiling point of water and coolant mixtures can be lower. Then you don't need to use as much antifreeze to achieve the same boiling point elevation as you would at sea level BUT the higher you go the colder the winters are so you need a higher ratio to prtect from freezing like 50/50 :lol:
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Re: Operating Temperature - what is the range?

Post by TXGOAT2 » Thu May 15, 2025 8:31 pm

Modern oil will allow operating at 200 F or so with no issues. Just be sure the system is kept full of coolant. 50/50 water and "green" antifreeze works very well. There is no practical reason not to use it, and use it as directed. Modern type valves are recommended for any Model T being driven on the road. Ford designed the T to run at 180 to 200 + F. With modern oil, there is a wide margin of safety at 200F as far as oil temperature. As long as the cooling system is reasonably clean and kept full of coolant, the engine will be fine at higher temperatures. Ford pointed out that temperatures near boiling gave the most efficient operation.


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Re: Operating Temperature - what is the range?

Post by TXGOAT2 » Thu May 15, 2025 8:32 pm

Fifty-fifty, unless you are touring the Yukon Territory in January.

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