Does your hood scoop allow water in?

I have a 2022 TRD Off-road and noticed that after it rains or I go through the car wash the fiber liner under the hood is wet. Is it normal for the hood scoop to allow water in and soak the fiber liner or does that mean the gaskets on the hood scoop need to be reapplied?

 

I've noticed this occasionally, but I assumed it was from the underbody flush. I certainly wouldn't expect the scoop to leak, but I can't say for sure.

 

I have been in some bad rains and no water intrusion on insulation. I got mine in April 2023.

 

I’m pretty sure mine leaks, because I’ve seen it wet after power washes.

edit: actually I’m sure it leaks, because you can tell it took in staining from the soap, bases on color and smell right after washing.

 

Water is coming in through the front grille, accelerated by the radiator fan if your engine is running. Why do you expect anything under the hood to stay dry in the rain or car wash?

 

Never noticed but the engine compartment isn’t sealed anyway.

 

Why have a hood then? Lol. The hood and the weather stripping is in fact designed to keep water off the engine. Lots of things under the hood don’t like being wet. In fact, my engine bay stays dry in heavy rain, although apparently, the scoop doesn’t like to get wet from certain directions. Not a big deal because the water is absorbed by the liner…but it looks kind of ratty now.

Thanks for sharing your research! I’ll keep this in mind next time I’m powerwashing!

 

I'm sorry, not possible, unless while in said heavy rain your truck is not moving, or only moving slowly. Now, a hot engine would boil off quite a bit of that water, but everything else subject to wheel spray and water forced through the radiator is going to be wet.

 

I don’t know…the radiator pretty much absorbs wind, the radiator fan isn’t driven when the radiator has airflow, (and it blows out, not into the engine as far as I know) so net effect is that water isn’t being forced in. While I can see misty water moving around a bit, there isn’t water pouring in during a rainstorm.

Anyways the water through the hood scoop isn’t pouring in either, but it’s good to know it can allow water to enter if parked on a slope nose down. I don’t wanna find out if mold can grow in that liner.

 

The air flow go towards the engine through the radiator, and the fan is always pulling air into the engine compartment although to a lesser degree at times, but the fan is always "driven" even when there's airflow through the radiator from forward motion, i.e. the air never blows outward from the engine compartment, if you still don't think this is true do a little research on the subject.

 

Hood is just there for reducing drag. Everything under the hood gets wet. Don't believe me? Aim a pressure washer at the front grille with the engine running.

I power wash the engine compartment on the way home from every 4-wheeling trip. Alternator, battery, fusebox, etc. all get thoroughly hosed down with the wand in the low setting. Better to be soaked than to have mud and sand in everything.

The fan is on a clutch which is driven by the water pump pulley. It's always spinning in the same direction pulling air across the radiator and onto the engine whenever the engine is running. Depending on how hot the clutch gets, the fan is either spinning at full engine speed or a subset of engine speed. The clutch is a simple fluid-mechanical device.

If you're concerned about mold, just rip out the hood liner. It's only sound deadening. Early 5th gens (like mine) don't have a hood liner. The millions of Tacomas built over the past three decades don't have it, either. If you can actually notice the sound difference and don't like it, install some waterproof adhesive insulation like Noico.

 

As a general caution to anyone, take care using the power washer. I power washed the engine bay on my 4runner once. I though I was being careful with it, but a month later I got a misfire on the #6 cylinder. Water got into the spark plug well and eventually messed up the spark plug insulator and started arcing inside the well. I ended up having to replace the plug and the coil.

There are places on the engine where water can accumulate and sit, the spot on the valve cover by #6 (driver-rear plug) is one of them. I’m sure the valley below the intake plenum is another. This is a good reason to keep the cover and the liner on, to prevent direct drip down on the engine when it’s sitting.

 

Water gets in trough the factory hood scoop. I replaced hood insulation after 9 years of use because it got mold from hood scoop water intrusion. Small amount not a huge deal. I used carpet plastic self adhesive sheet on backside of new insulation which directs small amount of water from under the scoop out instead of trough insulation. More than a year later - insulator looks brand new.

 

I didn't have the problem with my 2020 OR. My 23 ORP leaks heavily on the driver's side. Hose pressure only. I will have my hood up in the garage for a few hours. It comes through the acoustic panel, but pours out when I lift the hood. A good drip-dry is due.

Disappointed.

 

Just slap some silicone con carne alone the inside of the hood scoop seal. Have not noticed any leaking from mine.

 

Clear RTV can usually be found at the 99¢ store. Since engines can run just over the 200°F range, plus the sun beating down on it, I would say RTV would be the best choice as it is usually rated up to 500°F

If I get the heat shield/sound absorber off, I may just do that.

 

Interesting. Thank you!
After silicone, I bed I can do this

 

And then absolutely everything broke and came up through the floor.

There’s a certain beauty in those pictures…seeing the 4runner living its best life, for one last beautiful glorious second. Haha

 

Don't let fear or common sense stop you!

 

That’s one of those low IQ owners, huh?

 

Possibly an IQ of 4 (feet).

 

Does this let water in?

 

It looks like he picked a bad place to cross, snorkel notwithstanding.

 

I have the leak, but only noticed it after replacing the hood scoop from OEM white to OEM black. I might consider some sort of solution for it. I posted about it today here, hadn’t noticed this thread.

https://www.4runners.com/threads/hood-scoop-water-leak.37635/