engine temperature

Ok guys totally random question. What's the average temperature an engine has to be at before cooling is desired?

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COMMIT YOUR WAY TO JEHOVAH AND HE WILL ACT IN YOUR BEHALF. PSALMS 37:5

Ideally, it would never need cooling, making it more effient.

Way back in the old days, thermstats were to open around 160 f, the newer stuff around 105 c, mostly because the hotter running makes reducing pollution easier.

Ditto...
Too cool damages the engine.
So too does too hot.

Older 1960s-1970s engines like mine are low pressure (radiators; eg, 7psi) with ~82°C thermostats.
But newer engines run coolant (hence hotter) and higher pressures, and higher thermostats.

It really depends on the engine etc.

90-100c is "industry standard" regarding a target temperature.

Projects I have worked on will run upwards to 130c before things start shutting down. For instance, the AC will shut off around 135c and the engine will go into a form of limp-home at 140c

These numbers are referenced from some Gasoline port and direct injection projects I've worked on.

Temperatures above 100C are very dependent on pressure in the cooling system.  Darren we really need much more info about what you are asking to be able to answer this question.

And whilst systems may not boil until over 130°C (~270°F), that doesn't mean the engine components & systems appreciate it....

At mr idiot, i had no specifics in mind it was just a thought, so i thought i'd ask, thanks for the responses by the way fellas! Appreciate it!

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COMMIT YOUR WAY TO JEHOVAH AND HE WILL ACT IN YOUR BEHALF. PSALMS 37:5

In the real world, I don't think modern engines will run for too long at the 130c temps, think of the rubbish gaskets that go on most production vehicles these days.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Correct. But they can get that hot - hence why somethings will shut down to postpone destruction.

It assumes you are desperate to get home and hence ignore all the bells and whistles.
Unlike older vehicles with the ignored single "what's that O light?"...

I'd say 110C maybe 115C is the max any engine would run at. Of course, it depends where you take that measurement.... And I'm probably thinking more of competition vehicles.

Ceramic engines without "coolant" (and conventional gaskets) may run hotter....

Death valley and AZ on hot test we see upwards of 120c. But on the track you get coolant up to 130c along with the oil around 120c for quite some time.

And the guys that do hot fuel handling are looking at 130c coolant and 130c oil temps. But this is a forced condition highly unlikely to be encountered by a customer.

Do a search on GM camel mode if you haven't heard about this. Oldspark it is pretty much what you are talking about. Purpose is to get you home and pretty much scrap the engine in the process.

Thanks awdeclipse.
Camel mode - interesting... That might even get you home non-destructively.

I know a guy that got home ~250 miles in the outback without any coolant.
A kangaroo took out his radiator at dusk. (First dates with wildlife are often risky in the outback!)
After the initial stoppage, it was up to full speed; engine off & coast; repeat.
For ~250 miles.

As I recall, he replaced the radiator & coolant and she was fine (for a reasonable time...).

Not so lucky here, blew a water pump, limped home, about 40 miles, stopping at every petrol (gas) station to top, but of course it only reached the water pump level, not the cylinder head, replaced pump, 3 months later it decided it wasn't going anywhere, gaskets and head skim job. Hence my comments about running hot.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Not bad... I has a 3-month rule (ie, head gasket would blow almost to the day 3 months after the original cook/boil) but that was for my older iron heads.
Alloy heads aren't quite as robust.

But you can't run long with a air-head (so to speak). Hence the flat-out & coast tactic.

I'm surprised your head didn't crack assuming alloy & running for a while without head coolant. (Must've been a Jap Isuzu!)

Three months to the day and yes my water is oily sludge,hence crack head (sic), yes also for a close guess, a Mits 16 valve alloy head.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

No problems Howard - I have a 4G63 head I can send you.

4G63? Nice!

I lost my waterpump belt on the way to work one morning and I barely made it back home less then a mile in my GSX without pegging the coolant gauge. This was before the engine was even up to temp and driving home through a 20mph subdivision. When I parked it the car was just starting to gurgle.

Don't worry Peter it's probably easier for me to pick up another vehicle than have the head sent from Oz! Got my eyes on my friend's immaculate FTO for about £200. Boy can I do tricks with them and no transponder!

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Yeah - I just had to brag....
I got a head for $50 from a local PAP (Pocket A Part) when on special.
It's one of the Hyundai versions (slight improvements on the original).

I got one after talking to a mech that pointed out their "cheap" mods for 500HP... (They are one of the highest HP to capacity engines.)
(He and I were discussing the "crap" that occurs. He couldn't get over that I knew to soap & water bores.... LOL!)