Bonnet Vents & Water Ingress

[Anonymous]

There have been a few posts about this on another thread but I thought I’d start a new one as I have issues with mine. There are a number of different styles of vent but all fit the same hole and are in the same place for RWD cars. AWD cars seem to have the vents further down the bonnet. Mine let water in directly above the injectors which cannot be good long term.

My question is - do they actually need to be there for cooling/ventilation or are they just there for aesthetics? The holes in mine are tiny and there are only 6 each side (see photos) so can’t do much cooling or ventilation but are big enough to allow water ingress. I would like to find a way to partially close them off from the inside so water doesn’t drip onto the injectors but without causing pooling inside the vent housing.

Any ideas welcome!

 

[RPSN]

Great that you've started this thread on the subject GusA.

I take it the vents you have are the same or similar to the RWD 'shrouded' design that we have talked about on the 'MY16 5 year service' thread?
https://www.ftypeforums.co.uk/viewtopic.php?f=21&t=4906

If so, you are now the second V6 owner to recently confirm these vents are allowing water into the engine compartment (especially above the injectors).

On my own car it is quite normal for water to enter the engine compartment through the 'open mesh' bonnet vents i.e when it's raining (car isn't garaged) or when I wash the car, but instead of all the water running off the engine's plastic covers and away, some of it is getting to places where it shouldn't and is causing issues on some cars e.g. injector corrosion/failure etc. I've had no issues like this yet but that's not to say it won't happen as time goes by?

With regards to whether or not they are needed I would have thought that Jaguar designed them purposely for both aesthetics and cooling/ventilation of the engine compartment? I have read on another thread that by closing the vents off would be like detuning the engine? How much of this is true, I'm not sure?

If you still wanted to close them off, there are numerous high temperature tapes and sealants which could be used, although some of them can be very expensive e.g. some of the 3M products.

 

[PaulWildsmith]

yes, I know, even worse view when driving, but keeps it clean!

 

[Geminii]

Having the same vents on my V6S 2014 model I have been watching this thread with interest.

Rather than the option of blocking where the water is coming in with possible cooling implications would it be practical to stop where it is going?

Looking at GusA's 3rd picture I wonder if a shield could be designed to go over the 2 injectors or slide under the engine cover to prevent water getting there. A possible 3D printer design.

 

[chicb]

Screw or glue a plate to the underside of the vent to divert the water away. Not sure how much cooling/venting they supply, as if you put your hand beside the wheel arch after a run you will feel how much heat is coming out. (lots)

 

[Anonymous]

Great that you've started this thread on the subject GusA.

I take it the vents you have are the same or similar to the RWD 'shrouded' design that we have talked about on the 'MY16 5 year service' thread?
https://www.ftypeforums.co.uk/viewtopic.php?f=21&t=4906

If so, you are now the second V6 owner to recently confirm these vents are letting water seep through and into the engine compartment (especially above the injectors).

With regards to whether or not they are needed I would have thought that Jaguar designed them purposely for both aesthetics and cooling/ventilation of the engine compartment? I have read on another thread that by closing the vents off would be like detuning the engine? How much of this is true, I'm not sure?

If you still wanted to close them off, there are numerous high temperature tapes and sealants which could be used, although some of them can be very expensive e.g. some of the 3M products.

Yes, my vents look like the No3 Vent Finisher in the diagram on the earlier thread. As you can see from my pictures the holes are tiny and I cannot believe they add any meaningful cooling or ventilation so I think I will try and block them off somehow, although I want avoid any pools of water being stuck in the vent after it’s blocked off.

The vents look like they’re quite easy to remove with plastic spring clips holding them in place - anyone know if this is the case or are they more difficult?

 

[Anonymous]

yes, I know, even worse view when driving, but keeps it clean!

Haha! Mine lives in a garage when not being used so the water ingress is only a problem when driving in rain (often sadly) or washing the car. Still surprised by how much water gets in there.

The vents on yours are further down the bonnet I think so maybe JLR recognised the problem.

 

[Anonymous]

Screw or glue a plate to the underside of the vent to divert the water away. Not sure how much cooling/venting they supply, as if you put your hand beside the wheel arch after a run you will feel how much heat is coming out. (lots)

That’s a good idea although I might try taping a small sheet of plastic to the engine cover first to see if it actually works, will stare at it and scratch my head a little more tomorrow!

 

[scm]

The vents on yours are further down the bonnet I think so maybe JLR recognised the problem.

Maybe, but they redesigned the bonnet for AWD and fitted covers over the front suspension posts where the vents, er, vent.

 

[Anonymous]

The vents on yours are further down the bonnet I think so maybe JLR recognised the problem.

Maybe, but they redesigned the bonnet for AWD and fitted covers over the front suspension posts where the vents, er, vent.

Thanks @scm, any chance of a photo of what these covers look like?

 

[scm]

I'll do it tomorrow when it's a bit less dark!

 

[Anonymous]

I'll do it tomorrow when it's a bit less dark!

:lol: :lol:

 

[Timbo]

The awd drive bonnet is different to the rwd bonnet and yes they're are now covers over the top of the suspension strut to stop water ingress
as that is where the vents are now.
I would be very loathed to cover the vents up, they're there for a reason and not just for aesthetics

 

[RPSN]

Yes, my vents look like the No3 Vent Finisher in the diagram on the earlier thread. As you can see from my pictures the holes are tiny and I cannot believe they add any meaningful cooling or ventilation so I think I will try and block them off somehow, although I want avoid any pools of water being stuck in the vent after it’s blocked off.

The vents look like they’re quite easy to remove with plastic spring clips holding them in place - anyone know if this is the case or are they more difficult?

Personally, I wouldn't block off the bonnet vents as you may be doing more harm than good?

I mentioned earlier about another thread I've read which says that by closing off the vents would be like detuning the engine. This is that thread which was posted by 'SinF' (veteran member of the jaguarforums website)........

“I can confirm that hood vents are not ornamental, but essential for engine bay cooling during spirited driving. When I track the car, these vents are instrumental in keeping heat soak in check. However, for them to work optimally you need to remove engine cover.”

“I recommend you both remove engine cover and leave vents unblocked or potentially get engine power cut due to thermal issues. F-type is designed to be ultra-conservative in its approach to heat and will substantially cut power at slightest provocation. If you block these vents you will effectively detune your car during hot days.” https://www.jaguarforums.com/forum/f-type-x152-72/f-type-hood-vents-215551/

In any case, if you need to remove the vents it's easy to do but take your time and don't force anything too much as they're quite delicate!......Just push and hold the plastic spring clips in together at either side of the vent until they clear the inner edge of the bonnet cut-out. There's also one plastic clip at the pointed (narrow) end of the vent which needs to be pushed in. Then carefully start pushing the vent out by hand, working your way along it and repeating. Once this is done you can pull the vent out from the top surface of the bonnet. See my edited photo of your vent including marker arrows which depict where all the plastic clips are.

As I mentioned on the 'MY16 5 year service' thread', https://www.ftypeforums.co.uk/viewtopic.php?f=21&t=4906&p=48918#p48918 I'm currently experimenting with an idea on the large plastic cover that sits on top of the engine......this may help to prevent water from getting to the injectors etc? I'll be posting what I've done soon.

 

[Anonymous]

Yes, my vents look like the No3 Vent Finisher in the diagram on the earlier thread. As you can see from my pictures the holes are tiny and I cannot believe they add any meaningful cooling or ventilation so I think I will try and block them off somehow, although I want avoid any pools of water being stuck in the vent after it’s blocked off.

The vents look like they’re quite easy to remove with plastic spring clips holding them in place - anyone know if this is the case or are they more difficult?

Personally, I wouldn't block off the bonnet vents as you may be doing more harm than good?

I mentioned earlier about another thread I've read which says that by closing off the vents would be like detuning the engine. This is that thread which was posted by 'SinF' (veteran member of the jaguarforums website)........

“I can confirm that hood vents are not ornamental, but essential for engine bay cooling during spirited driving. When I track the car, these vents are instrumental in keeping heat soak in check. However, for them to work optimally you need to remove engine cover.”

“I recommend you both remove engine cover and leave vents unblocked or potentially get engine power cut due to thermal issues. F-type is designed to be ultra-conservative in its approach to heat and will substantially cut power at slightest provocation. If you block these vents you will effectively detune your car during hot days.”

In any case, if you need to remove the vents it's easy to do but take your time and don't force anything too much as they're quite delicate!......Just push and hold the plastic spring clips in together at either side of the vent until they clear the inner edge of the bonnet cut-out. There's also one plastic clip at the pointed (narrow) end of the vent which needs to be pushed in. Then carefully start pushing the vent out by hand, working your way along it and repeating. Once this is done you can pull the vent out from the top surface of the bonnet. See my edited photo of your vent including marker arrows which depict where all the plastic clips are.

As I mentioned on the 'MY16 5 year service' thread', https://www.ftypeforums.co.uk/viewtopic.php?f=21&t=4906&p=48918#p48918 I'm currently experimenting with an idea on the large plastic cover that sits on top of the engine......this may help to prevent water from getting to the injectors etc? I'll be posting what I've done soon.

That’s useful thanks. I don’t track the car and will never push it to the point that heat soak is going to be a problem.

It’ll be interesting to see what you do with your cover.

 

[RPSN]

That’s useful thanks. I don’t track the car and will never push it to the point that heat soak is going to be a problem.

It’ll be interesting to see what you do with your cover.

Even though you don’t track the car and will never push it to the point that heat soak is going to be a problem, I’d still be extremely weary of blocking off the vents especially after reading the info in the post I included from the jaguarforums website.

Also on the same link https://www.jaguarforums.com/forum/f-type-x152-72/f-type-hood-vents-215551/.......

“The problem without the open area hood vents is you are relying on the thermal transfer of the engine compartment heat through the aluminum bonnet that is a diffusion process to the air above it and is limited by the temperature of that air. Hood vents expedite that process”

and......

"Agreed, the vents do work to release heat from the engine bay but they could do with a lot more air flow"

I need to take my car out for a few more ‘spirited’ drives before I post what I’ve done to the engine cover. May take it out later if the roads dry up nicely.......gritters have been around lately aaargh!

 

[PhilB]

Interesting thread.
Looking at the pictures of the inside of the vents I think given the few holes and the size, the effect of cooling under the bonnet would be negligible.
I think they are drain holes so water doesn't pool in the vents.
I have had two XE's with the 340hp and the 380hp V6's and neither had vents in the bonnet.
The V6 is installed in other JLR models and again no vents.
They are supercharged not turbocharged so the heat under the bonnet isn't excessive like a turbo can be.
Do what you must but if that's JLR's idea of cooling vents then it seems pretty minimal to me.

 

[scm]

Thanks @scm, any chance of a photo of what these covers look like?

Here you go, complete with a few drips from when I opened the bonnet ... :? Left hand side was bone dry.

 

[RPSN]

Interesting thread.
Looking at the pictures of the inside of the vents I think given the few holes and the size, the effect of cooling under the bonnet would be negligible.
I think they are drain holes so water doesn't pool in the vents.
I have had two XE's with the 340hp and the 380hp V6's and neither had vents in the bonnet.
The V6 is installed in other JLR models and again no vents.
They are supercharged not turbocharged so the heat under the bonnet isn't excessive like a turbo can be.
Do what you must but if that's JLR's idea of cooling vents then it seems pretty minimal to me.

Here’s another photo of the upper side of what I think are the same vents (correct me if they’re not GusA?).

Although the venting area isn’t that big, I’d say it would definitely help with the cooling/ventilation of the engine compartment.

As previously mentioned on the jaguarforums link.......“the F-type is designed to be ultra-conservative in its approach to heat and will substantially cut power at the slightest provocation.”

 

[RPSN]

Here you go, complete with a few drips from when I opened the bonnet ... :? Left hand side was bone dry.

As those plastic covers are for the AWD version they wouldn't be suitable for the RWD.

As Timbo said......."The awd drive bonnet is different to the rwd bonnet."

If you look at the light coloured watermark on the passenger side of GusA's engine cover (this is directly below the bonnet vent) you'll find it's in a different location to the plastic cover which is on the top of the suspension strut on your car.