Why is the hood so hot?
3 Answers
Reasons why the hood gets very hot: 1. The engine temperature rises rapidly just seconds after starting: Because the engine needs to reach a certain temperature to perform optimally. 2. Combustion of the air-fuel mixture in the cylinders: Rapid burning and expansion after ignition to drive piston movement generates enormous heat. 3. Wind generated by vehicle speed and the fan blow radiator heat into the engine compartment: Since the hood is metal, it heats up quickly. 4. Heat from engine operation and the radiator is dissipated to the hood: As long as the temperature gauge on the dashboard does not indicate overheating, there is no problem.
After driving on the highway last time, I noticed the hood was so hot you could fry an egg on it, which is actually normal. The engine works like a small furnace, with normal operating temperatures around 90 degrees Celsius. After high-speed driving in summer, the engine compartment temperature can exceed 100 degrees. However, if it gets abnormally hot after just 10-15 minutes of city driving, you should pay attention. I usually check if the coolant level is sufficient, whether the radiator is blocked by leaves or willow catkins, and if the cooling fan is functioning properly. Especially for older cars, aging wiring or minor leaks in the cooling system can affect heat dissipation. Occasionally, an overly hot hood might also be related to insufficient engine oil, so regular fluid checks are important. If you notice a temperature warning light or unusual odors, it's best to seek professional help immediately.
I've encountered abnormally hot hood situations, with the main issue stemming from the cooling system. A faulty radiator fan is a common culprit, especially when it fails to activate during traffic jams, trapping all the heat in the engine bay. Insufficient coolant prevents heat dissipation, and a leaking radiator makes things worse. Last time when helping a friend inspect his car, we found his radiator clogged with debris like a sieve - temperatures dropped noticeably after cleaning. A stuck thermostat is also troublesome as it fails to open when needed, disrupting coolant circulation. I recommend drivers regularly monitor the coolant temperature gauge needle position, routinely flush radiator fins (particularly after long trips or during spring/summer when poplar catkins are abundant), and replace coolant every two years for optimal maintenance.
