Let the car cool off with the hood up ?

Messages
17,501
Location
Clovis, CA
How many of you let the car cool off with the hood up during the summer ? I know it's totally unnecessary, but I've always thought of cars as being alive in some way. I know I'd surely appreciate it if my owner raised to hood and let me cool off. smile2
 
Messages
1,429
Location
quebec canada
The car benefit by letting it cool off.big rig have to do it now a days with oil in the 225 degree faren.you climb the i77 highway between nc and va and stop at the top and dont cool it off is a sure way to cook everything.rule of thumb is you let it cool of same time it take to warm it up when its cold to operating temperature
 
Messages
2,408
Location
CA
?, only if you're cooling it off in terms of needing to perform some maintenance. Otherwise, the car is not a human, it's meant to run at 200+ degrees. Which as you know is hotter then ambient unless you are driving on venus. So your car is actually "freezing" and cold and getting the sniffles all the time when it's off, so you're doing it no favors. If you look at some of the Prius engine design, they specifically insulate stuff to make sure the engine stays warm and hot enough as the engine doesn't get to run enough of the time. In comparison, look what they do for F1 cars. Before they start up, they have their fluids preheated to 200+ degrees, and tires preheated and so on. Your "car" in terms of the engine would be happier if it were 200 degrees ambient, not 100degrees. So if you wanted to treat your car, you need to install warmer blankets and heaters so on to keep your car hot while it's off.
 
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Messages
10,738
Location
MA
Originally Posted By: cknight49090
nobody does this period ocd ..........
Yep. This is crazy talk. If I did this, I'd worry about the hood release cable breaking or the hood latch springs getting worn out because you're opening/closing the hood so much.
 
Messages
1,909
Location
Tracy, CA
My friend does this all the time. I think he learned it from his father. You go over to both of their homes and the hoods are up. Never did get a good answer for why. When I was a volunteer with the CDF (now known as Cal-Fire), we used to open the hoods of the trucks that were being used as pumpers to dissipate the heat. I really don't think it's necessary to do this for a passenger car. However, I've started to open and leave the hood open when I know I'm going to be working in the garage a bit later after I park. It's just a comfort thing for me. I figure it's easier to open the garage doors, turn on a couple of box fans and let the cooler evening breeze blow out whatever hot air has risen to the ceiling than to try and have the cool air try to cool off that huge, insulated heat sink under the hood. OCD? Perhaps so. Makes a difference? At least in my feeble mind it does.
 
Messages
4,109
Location
Central Virginia
A modern car, truck or big truck should be able to handle heat transfer w/o opening the hood. I would use a bry bulk blower for about 1 1/2 hour at a time w/engine at 1200 and never an issue. The fan kicks on plenty, but doesn't hurt anything.
 
Messages
4,837
Location
Central Texas
I do regularly. Have for a few decades now. Got in the habit with the old SAAB 900T because the hood sat right on top of the engine + plus the turbocharger was only oil cooled. I'd open the hood, dump the heat for a few hours then pull her into the garage...which was already hot enough. Why heat it up even more?
 
Messages
680
Location
Hawaii
I don't think it's necessary to do this. My car's cooling fans turn on at certain temperatures and stays on even when the engine is turned off. It'll turn off when it's cooled down, typically at 200F. I live in a warm climate and it rarely stays on when engine is off.
 
Messages
566
Location
Ky
Only if I track race or something like that with oil temp really high then stop, I would idle it for a minute or two before shut off. That is the extent of it. Open hood cool down is a thing of past. smile
 
Messages
19,686
Location
Sunny Florida
Originally Posted By: Merkava_4
How many of you let the car cool off with the hood up during the summer ? I know it's totally unnecessary, but I've always thought of cars as being alive in some way. I know I'd surely appreciate it if my owner raised to hood and let me cool off. smile2
High underhood temps can indeed accelerate the deterioration of some parts. I have cooled the car down many times when drag racing by opening the hood, IAT temps drop really fast then, in my platform that means a nice couple of tenths...
 
Messages
9,740
Location
Ontario, Canada
Originally Posted By: SteveSRT8
Originally Posted By: Merkava_4
How many of you let the car cool off with the hood up during the summer ? I know it's totally unnecessary, but I've always thought of cars as being alive in some way. I know I'd surely appreciate it if my owner raised to hood and let me cool off. smile2
High underhood temps can indeed accelerate the deterioration of some parts. I have cooled the car down many times when drag racing by opening the hood, IAT temps drop really fast then, in my platform that means a nice couple of tenths...
+1 At autocross or lapping, lots of people leave the hood up between runs if its a hot day. You atleast don't want to come in and shut it off right away, I'd try to let it run until the cooling fan turned off.
 
Messages
40,715
Location
Great Lakes
Originally Posted By: cknight49090
nobody does this period ocd ..........
Agreed. Maybe if you're at the track, but certainly not after a typical street drive.
 
Messages
43,667
Location
'Stralia
Originally Posted By: cknight49090
nobody does this period ocd ..........
I wish they'd spell that cdo...but still wouldn't do what the OP suggested.
 

pbm

Messages
8,890
Location
New York
Originally Posted By: R80RS
I never do this with my cars, but I usually raise the hood on my air cooled lawn tractor after I shut it down for the day.
I also do this with my lawn tractor for about a half hour before putting her back in the shed. I have done it on my Cruze 1.4T in the garage after a long drive in hot weather.....probably isn't necessary.
 
Messages
8,484
Location
Champlain/Hudson Valley
The only time I've ever opened the hood for a heat related reason was because I had to work on the car. I also ran a big fan on the engine to hasten the process. As a kid I remember seeing police cars with their hoods popped open when the cops were directing traffic or the like. K.
 
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