Bonnet Vents & Water Ingress

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Deleted User 1715

Post by Deleted User 1715 »

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!

7A5F7040-B934-4E54-87A9-1CCEFB6DC644.jpeg

81D2D414-4742-49BA-A5A2-78DEB1573D25.jpeg

7D313F73-7A6B-4962-A06E-F3B87702157C.jpeg

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RPSN
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Post by 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?
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.
Last edited by RPSN on Fri Nov 27, 2020 12:53 am, edited 1 time in total.
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PaulWildsmith
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Post by PaulWildsmith »

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

2020-11-26 11.17.47.jpg

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Geminii
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Post by 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.
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Post by 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)
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Deleted User 1715

Post by Deleted User 1715 »

RPSN wrote: Thu Nov 26, 2020 10:28 am 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?
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?
Deleted User 1715

Post by Deleted User 1715 »

PaulWildsmith wrote: Thu Nov 26, 2020 11:25 am 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.
Deleted User 1715

Post by Deleted User 1715 »

chicb wrote: Thu Nov 26, 2020 12:59 pm 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!
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scm
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Post by scm »

GusA wrote: Thu Nov 26, 2020 6:22 pmThe 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.
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Deleted User 1715

Post by Deleted User 1715 »

scm wrote: Thu Nov 26, 2020 6:30 pm
GusA wrote: Thu Nov 26, 2020 6:22 pmThe 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?
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