My car stood in the sun for three hours after a gentle motorway run of 40 km. When we got in it the dash temp gauge read 39 degrees C Ambled back at gentle 70 and at home thought I would check my oil. Well I still have red but not blistered marks on two fingers and one thumb off the bonnet prop !!!
Forget frying an egg this would have fried a batch of chips.
Can the plastic parts under the bonnet stand any temperature or will my car shut down in disgust one of these days with a dash message "stuff this too hot"
What are they designed to cope with ?
Appreciate your views. thanks. PS car lives near Murcia.
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has said vehicle got a radiator?
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Thats nothing. The outside temp guage of our hire cars in Israel regularly reach 41C when parked up during the day and the under bonnet temp of a car on a cold day in the UK after a long motorway run will be more than warm. A summers day in the middle of Iraq will be show it a little warmer - say 50C?
The manufaturers test their cars in extremes of heat and cold to find out if the plastics will survive. They usually do!
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For a brief while, many years ago, I did some technician work for the climatic wind tunnel at MIRA.
Among the cars I instrumented was a Land Rover vehicle which was being assessed for the suitability of the facelifted front panelling, as it affected the airflow over the radiators. I don't know how hot everything gets in there, but, one of the sensors I had fitted fell off part way through a hot test. Obviously, the guilty party had to rectify the fault, without hindering the test too much.
The wind tunnel was set to cool down, and slow down, and after a while, I was allowed to go in. By the time I had walked from the door to the vehicle, my whole body was sweating in a way it's never done before, or since! Most unpleasant!
So, yes, the underbonnet temperature limits will be beyond our endurance, and yes, the testing is also fairly extreme!
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When you think Tony, that the highest temperature ever recorded was 57c in Libya, 39c can seem quite cool : )
The coldest temp ever recorded was -90c in Antarctica !
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Had no problems in Kuwait, Qatar or Saudi with shade temperatures up to 50C - cars in the open even higher temps; but caution needed touching steering wheel, gearshift, etc., if you haven't used a folding sunshade in the windscreen.
In passing - lived in Murcia for six years with cars in the open no problem - now moved to Galicia (don't ask about the rain!).
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yeah but doesnt a radiator kick in around 99c so it dont matter how hot the ambient heat is so long as the rad and the water pump is working?
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There are loads of proving grounds out in the desert near Phoenix where they just run new cars non-stop to see how well they handle the (45C+) heat. Don't think it's really a problem. Even our aircraft are air-cooled and will buzz around doing touch-and-go's all day without overheating, although it can be fairly borderline sometimes.
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The interior can get very hot. I have a digital thermometer that reads up to 49 deg C and it has often shown "_ _ . _" on the dial (i.e. over max reading) in this hot weather.
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When I worked in the Middle East I've seen thermometers directly in the sun nudge 70 deg C, Cassette tapes and Pens left in cars melted into shapes only Salvador Dali could have imagined. Ive also seen lighters left out on tables in the sun explode in a most impressive manner.
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Ive also seen lighters left out on tables in the sunexplode in a most impressive manner.
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Left one in the car once. It went bang, covering the interior with sharp bits of plastic.
So not only did I toast my bum when I got back into the car, but also had a few sharp bits of Bic stuck into it as well!
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>>so it dont matter
It's not automatic that this is true.
The cooling system needs to be designed to reject heat, even when the ambient temperature is high, at a greater rate than the powertrain can generate it, and have a comfortable margin to account for sludge in the water system, and normal partial blockage of the radiator. It's an outcome of good design and testing that this happens.
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Turbo chargers regularly push out charge at over 90C (200F).
A standard car exhaust gets a lot hotter than 40C. I don't think any ambient temperatures are really going to affect the engine and plastics when you consider the heat that is generally generated under the bonnet under "normal" conditions.
The battery might complain though which is why some manufacturers still have them in the relatively cool boot.
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By eck---correction to initial post. I've just noticed one of my fingers has got a damn blister !!!. Now that's not funny.
Who can I sue ?
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The manufacturer. That way, in the future, your turmoil and suffering will lead to a note in the manual (and if you're lucky, a sticker under the bonnet), cautioning that the engine may be hot if left in the sun. :)
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After a lengthy speedy run once, on a hot day - a fair amount of miles at 150kmh plus, I encountered some roadworks, and had a 10 minute wait.
Because the car had been working hard, and because it had gone from hard work to quick stop, the underbonnet temp was so hot the car refused to start, and the heatguage was right up deep in the red.
In hindsight, I should have turned the engine off, but let the electric fans keep turning.
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Many moons ago my employer's requirement was that their cars should be capable of continuous idling (without the coolant boiling) in ambient temperatures of 40 degC for home and general export markets and 50degC for cars specifically destined for Iran. Although we recorded underbonnet temperatures during the tests I'm afraid I can't remember (it was a long time ago and I'm a septuagenarian now) what they reached, but obviously they would have been considerably higher than the test ambient temperature. By the end of the test the coolant temperature would approach 120 degC. The cars were also designed to be capable of being driven continuously at maximum speed in the aforementioned ambient temperatures without the coolant boiling (120 degC) and without oil temperatures (engine, gearbox and rear axle) reaching levels at which they would degrade. I vaguely recall 200 degC being the allowable stabilised maximum for the oils.
Edited by L'escargot on 31/07/2008 at 08:46
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I left an unopened can of coke in a hire car when I was working in Basildon one summer.
When I got back to the car, the can had exploded, was almost empty and there was a sticky (but dry) residue over the interior
I often wondered how much heat is required to explode a can of coke
MVP
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I remember wearing shorts in a leather seated Mercedes left out in 40C temperatures. Painful is not the word.
Never had leather since...
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I returned once to my car in Qatar to find a temperature of 44 degrees C - This was not high summer but the middle of November.
Temperatures in summer regularly exceed 50 degrees C.
Just try to imagine what it is like in the glass goldfish bowl cockpit of an non - airconditioned helicopter being held waiting in that sort of heat by ground control for five or ten minutes.....
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when jaguar were road testing the original batch of XJS cars they drove them round and round the track
the battery melted (it was in the front)
that why the battery was moved to the boot in those cars from then on
I think the V12s got asbestos around the engine side of the passenger footwell as well
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How hot can cars get ?
Well , circa 1989, my '74 Ford Landau, black bodywork, black vinyl roof, black vinyl seats, about 150 miles / 5 hours up country in the south of Brazil on a mud road. Miles from nothing at all. Height of summer. Middle of the day. The AC packs up. Didn't have any means of measuring the temperature but I'm guessing 40c + and nigh on 90% humidity.
That was fairly hot.
Finally got back to the office to find a fax from my boss in the UK moaning that he couldn't contact me and implying that I must have had a nice day at the beach. Grrrrr.
They sacked him shortly afterwards so I suppose I got over it !
;-)
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the battery melted>>
A lot of Jags have electric fan cooled batteries.
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