How dry does the engine bay stay in a downpour?

[The motor guy]

I once recall driving through a huge downpour on my way home from work. The rain stopped once I got home, so I decided to pop the hood and see how much stuff got wet and was surprised it was dry as a bone. Now I did drive through the entire neighborhood once it stopped raining, so I'm not sure that was enough air flow to dry things out beforehand or what. Opinions?

 

[Brian123]

I once recall driving through a huge downpour on my way home from work. The rain stopped once I got home, so I decided to pop the hood and see how much stuff gor wet and was surprised it was dry as a bone. Now I did drive through the entire neighborhood once it stopped raining, so I'm not sure that was enough air flow to dry things out beforehand or what. Opinions?

gor or got!

My thought is the engine bay is Hot and the engineers designed the car in a way that the engine would not get wet!

 

[The motor guy]

gor or got!

My thought is the engine bay is Hot and the engineers designed the car in a way that the engine would not get wet!

Maybe their is enough heat in general under the hood to evaporate things

 

[Brian123]

Maybe their is enough heat in general under the hood to evaporate things

What you said is what I was thinking, but I could not put it to words!

 

[KrisZ]

The engine bays are designed to stay relatively dry, that’s why you have seals around the hood line, and water drains and channels to divert the water away.

 

[burbguy82]

mine does not, but I have hood louvers cut into the hood on 2 vehicles, and the other two stay dry as a bone.

 

[atikovi]

I once recall driving through a huge downpour on my way home from work. The rain stopped once I got home, so I decided to pop the hood and see how much stuff got wet and was surprised it was dry as a bone.

You have a hood over the engine, or maybe I don't get the question. You also have a trunk lid or liftgate on the back of your car to keep the trunk dry too. It's not magic.

 

[burbguy82]

I would assume that some water gets in via airflow through the radiator, but would be quickly evaporated from said airflow and heat.

 

[D60]

I don't think it much matters unless you have heavy water falling down on engine to flood deep well spark plug tubes or a distributor.

Obviously, intake has to be shielded fairly well.

 

[Jetronic]

You have a hood over the engine, or maybe I don't get the question. You also have a trunk lid or liftgate on the back of your car to keep the trunk dry too. It's not magic.

but the trunk is closed on all sides, the engine bay is open at the bottom and very leaky up front. No it's not magic, but I can see where the question comes from. And it does get dusty in there

 

[Jetronic]

I would assume that some water gets in via airflow through the radiator, but would be quickly evaporated from said airflow and heat.

I'd be more concerned with spray from driving through standing water. It doesn't all spray onto the curb....

 

[benjamming]

Which is why those pesky (and all too often flimsy & poorly designed) shields (no, not the up top vanity covers/advertisements) are actually important. I wish more people would pay attention to & actually handle those with care. Alas, these are some of the first items no longer available as vehicles "age out".

 

[skyactiv]

It's called wheel wells.

 

[joekingcorvette]

Your front wheels get the engine bay more dirty and wet than from a downpour. My honda Civic with an engine plate on the bottom will stay more dry than my Ford F-150 which seems to have more open areas where water can splash up.

 

[SHOZ]

Sounds like time for a Go Pro!

 

[atikovi]

but the trunk is closed on all sides, the engine bay is open at the bottom and very leaky up front. No it's not magic, but I can see where the question comes from. And it does get dusty in there

And so is the engine bay. It's open at the bottom buy rain doesn't fall up from the road.

 

[Jetronic]

And so is the engine bay. It's open at the bottom buy rain doesn't fall up from the road.

spray from the front wheels

 

[atikovi]

spray from the front wheels

Fender liners prevent that, not to mention the front wheels are at the side of the engine bay.

 

[Jetronic]

Fender liners prevent that, not to mention the front wheels are at the side of the engine bay.

No the fender liners don't. Undertrays do if fitted. Spray goes sideways and up same as it does onto the sidewalk. And there's holes in fender liners for steering linkage and drive shafts.

I've had issues with customers leaving ioff undertrays and water getting into the timing belt cover and then freezing. Guess what, when the pulley valleys are filled with ice, the timing belt jumps....

The engine bay is a wet area, but if the engine is hot it dries quickly.

 

[John105]

Oddly my wife's 2011 GM has a power steering cooler. When there is a downpour, steam comes from that area (it's mounted in front of the radiator).

If one looks at modern cars today, there is either nothing between the outside world and the radiator through the grille, like her car, or there's a barrier (many new cars the grille is just an ornament).

I recall being a kid and my parents drove through a downpour on the Storrow Drive (I remember the Citgo sign). Toyota stalled, as did some other cars around us. My dad said we'll just wait a little and be on our way soon after the plug wires dry out. Back in the days when there was a coil and distributor...