Is it bad to open the coolant reservoir when the engine is hot (i.e. parked about 15 minutes ago?)
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Is it bad to open the coolant reservoir when the engine is hot (i.e. parked about 15 minutes ago?)
I have had this happen before, and had a small amount of coolant bubble up and then empty out of some sort of pressure valve on the underside of the tank ...
Bad news, or just "don't do it again" type of stuff?
Bad news, or just "don't do it again" type of stuff?
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Don't do that again!!!
AFAIK, the coolant tank is under pressure when hot. When you open the cap, you release the pressure. As the pressure drops, the coolant turns to vapor (pressure keeps it in a liquid state in the sealed system). Vapor escapes out of the tank, and will burn you BEYOND BELIEF. Think 3rd degree burns all over your arms, face and chest. Steam or coolant in it's vaporized state is HOTTER than boiling water...MUCH MUCH hotter.
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Indeed - but you'll all be happy (or perhaps not) to know that I didn't get any burns.
I was afraid something might "happen" and opened the thing VERY slowly while wearing work gloves. When I heard a fizz, I stopped and let it release down through that valve thing and onto the ground. Nothing got onto me. Thanks for you guys' responses, though, at least I don't have to worry I f'd up the car!
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it's the resevoir, coolant doens't generally flow into it from the radiator. My understanding was
that the resevoir only is used to fill the radiator/pump/hoses/block and is not generally pressurized in our cars. It's not like the cap that most cars have on the radiator... i could be wrong though.
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Years ago I used to work for a limo service...
We had a car break down, and they dispatched one of their mechanics to investigate. Poor guy got there less than 30 minutes after the car broke down, thought the car had cooled sufficiently, and proceeded to open the radiator cap.
Next time I saw that mechanic, he was covered in bandages. His face, neck, arm, and the upper part of his chest were permanently scarred. :-( It's a nasty mistake to make when working under the hood.
Next time I saw that mechanic, he was covered in bandages. His face, neck, arm, and the upper part of his chest were permanently scarred. :-( It's a nasty mistake to make when working under the hood.
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