Defender Engine Bay Heat - LH guard vent [Archive]

rainman

23rd February 2012, 03:49 PM

I remember seeing a picture on the forum of a Defender with a vent cut unto the left hand guard behind the wheel arch to provide an exit for hot air from the engine bay, but for the life of me I can't find it again.

I believe member uniformed has done the mod. Has anyone else? Does anyone have any pictures, or information on the vent used to cover the hole?

Thanks in advance,
James.

rick130

23rd February 2012, 05:32 PM

Yep, Serg did it and it works.

I keep saying I'll do it to but haven't got around to it yet.

[edit]Here's a pic.

https://www.aulro.com/afvb/

weeds

24th February 2012, 09:09 AM

Yep, Serg did it and it works.

I keep saying I'll do it to but haven't got around to it yet.

[edit]Here's a pic.

http://img713.imageshack.us/img713/27/stuff017a.jpg

OK what is Serg's username?

rainman

24th February 2012, 02:23 PM

OK what is Serg's username?

uninformed

rick130

24th February 2012, 02:55 PM

A mate of Sergio's who has a 200Tdi as his farm vehicle no longer uses that position for the air intake but it still has the grille in place.
Serg could reach down and feel the air coming out and reckons the flow of hot air coming out at @ 40km/h is pretty high, so he was sold on the idea.

His engine temp at high load/speed dropped slightly too after doing the mod, if he chimes in he can tell you by how much.

This was after we'd tossed the idea around for a few years as IMO GU Patrols suffer from a similar problem re exhausting the air from the engine bay.

uninformed

24th February 2012, 03:13 PM

yep thats mine. It has worked a treat. As Rick had said, we had talked about the engine bay heat, and his findings were that bonnet vents or gaurd top vents no good for exit air. My mates truck runs these on both sides and it runs VERY cool. Mind you he has modded his truck alot, has more room in his engine bay by rearanging the ancilaries etc. His vent holes act as a double feature. If he needs to work on the side of his engine, he simply removes the vents and this gives him access to his guard/wing nuts (he changed his bolts to stud so the pannel can be offered up to them and rest on them, rather than the dumb idea of jugle the guard and bolt by himself) his gaurds can come of in about 5 mins.

While driving around his property from 0-50/60km hr I was able to reach out and feel the hot air flowing out of the left hand guard (turbo side of coarse)

My 2.8tgv is making more power so more heat, my cooling system is in very good condition and I am running a 82c stamped thermostat. In most normal conditions on the Gold Coast, it runs at 89-91 on a VDO gauge. Now with the hole cut it will sit on 83-85 around town and 89 on the HWY.

taking into consideration ambieant temp and humidity and watching the gauge very closely before and after the hole was cut, it now has just that little more buffer for temp and seems to drop quicker when load is reduced.

I did find that putting the grill on the hole added 1c to the range, but this still lower than before the hole was cut at all.

I would make the hole the same shape but go down a little further (will help with guard bolts)

I think someone mentioned that wire grill would flow better than perforated sheet (but thats what I had)

The only downside I can see is maybe in deep water crossings....but I havent tried so dont know if water wants to pour in there (I doubt with forward motion it will want to, but sometimes a water crossing becomes a forward-stop-reverse action.....)

weeds

24th February 2012, 03:24 PM

over to you rainman.........

uninformed

24th February 2012, 05:58 PM

Just to add, my truck was a 300tdi so intake is on the drivers side, I just cut the hole myself on the left side. I marked it out and used hole saws for the radius corners then a 1mm cutting disc in a grinder for the straight cuts. Cleaned it up with a die grinder. I used some 2-3mm perforated sheet, but I put a 20mm wide band of 2mm flat plate around the perimeter to make it and the now cut pannel more ridged. I think they call the bolts water tank or tank bolts, they have a proportianly larger head for shank size, are domed with philips. Most places will only have zinc, but I lucked out and got stainless. I used zinc nuts and welded them to the back of the grill. Plastic washers under the bolt heads. Even though the grill is bigger than the hole, it is very easy to remove and refit. They grill was cleaned and etched primed, then coated with high temp black (K&H)

My mates truck now has his air intake ontop of the grill where the heater/vent normally collects......LR should have done it this way. He also removed the airfilter housing from the engine and mounted it over at the intake point...His words are it now wont get the crap shaken out of it by the motor.

isuzurover

9th January 2013, 11:01 AM

Nice work Serg. Only just saw this thread.

rick130

9th January 2013, 03:35 PM

Yep, he did a nice job.

Those wheels look good too :angel:

redrovertdi

9th January 2013, 04:35 PM

I did the same to my 300tdi, when the thermos[no viscous]kick in you can feel the hot air blowing out

Naks

12th January 2013, 12:02 AM

Looks like a cool mod.

Would the outlet be on the same side for a Puma, since the turbo is on the right/driver's side?

2stroke

12th January 2013, 07:04 AM

Well that's a mod I'll be sure to do once the new head goes on. I guess you lower the pressure by letting out the hot air and more cool air has no choice but to come in via the radiator.

rainman

6th March 2013, 07:43 AM

By the time I got the angle grinder going I was shaking so much I almost had to stop.

https://www.aulro.com/afvb/images/imported/2013/03/1005.jpg

https://www.aulro.com/afvb/images/imported/2013/03/1006.jpg

Now to put the mesh on....

James.

uninformed

6th March 2013, 09:07 AM

weeds

6th March 2013, 09:18 AM

rainman

6th March 2013, 09:21 AM

Jebus :o Id be nervous too if my truck looked brand new!.........There are benefits from having an old beater, it doesnt phase me one bit to tinker and play with it now :D

Very nice work James. Did you put the foil insulation on the bulkhead?

cheers
Serg

Hi Serg,

Thanks :). I did the insulation during the rebuild before I put the guards back on. Even then it was a bit of a mission, but worth it.

James.

rainman

6th March 2013, 09:23 AM

i guess that counts out making it look like a big rig with twin snorkles

Damn - could I have run two turbos then? :p

James.

flagg

6th March 2013, 09:47 AM

How much does it increase noise in the cabin?

rainman

6th March 2013, 10:00 AM

How much does it increase noise in the cabin?

Sorry flagg, do you mean having the hole in the guard? Serg or redrovertdi might have to answer that. I haven't driven it since I cut it out.

james.

flagg

6th March 2013, 11:11 AM

Sorry flagg, do you mean having the hole in the guard? Serg or redrovertdi might have to answer that. I haven't driven it since I cut it out.

james.

Yep, having the hole there.

redrovertdi

6th March 2013, 12:34 PM

I didnt notice any extra noise, but i always have the drivers window down and the firewall vents open with the radio loud. Mates county has 4 round holes with mesh in the bonnet sides near the windscreen[non opening firewall vents], i didnt go that way in case i ended up with the engine bay hot air coming in under the windscreen. I will probably install some small scoops in the front corner of the guards just beside the headlights[ i already have guard top scopes but one is dedicated to fan/heater pick up so doesnt get near turbo 300tdi]. I wrapped my exhaust and turbo in heat cloth and that also made a difference, i was told not to wrap my 3inch exhaust as it would shorten the life and cause the metal to crystalise and fatigue[i thought that was stainless only but not according to the exhaust place[whom has done lots of custom work for me over the years]]
Richard

rick130

6th March 2013, 02:53 PM

[snip]
I wrapped my exhaust and turbo in heat cloth and that also made a difference, i was told not to wrap my 3inch exhaust as it would shorten the life and cause the metal to crystalise and fatigue[i thought that was stainless only but not according to the exhaust place[whom has done lots of custom work for me over the years]]
Richard

My 3" pipe's been wrapped for five years now and it's been fine.
I went all the way from the dump to the back of the t/case.

Inc tipped me off to mild steel being OK as I was told the same thing as you.
Inc was a fitter on the old Manly Cats and said their mild steel exhausts post turbo were wrapped all the way and it was never an issue

uninformed

6th March 2013, 03:56 PM

noise didnt change.....then again I have a fist size "vent" in my bulkhead foot well :(

I like Jame's vent size better, that is, he made it go down lower on the pannel for more area.

rainman

6th March 2013, 04:00 PM

noise didnt change.....then again I have a fist size "vent" in my bulkhead foot well :(

Bahahahahaa! :Rolling:

Nera Donna

6th March 2013, 07:19 PM

uninformed

6th March 2013, 08:09 PM

I’ve been toying with the idea of buying a ‘Southdown’ snorkel for a while now, which would leave the original intake open as a vent. I just can’t bring myself to commit to cutting a hole in the top of the guard. This might be a solution for somebody out there?

well here is another solution. kneel on the black plastic cover, drivers side, top of gaurd. When it cracks and breaks, remove it with the intention of replacing it.....then after a month or so, convince yourself its helping vent the engine bay :D

vents cut in side of guard definitly work, left being ideal as it is turbo side.

Nera Donna

6th March 2013, 08:15 PM

rick130

7th March 2013, 06:45 AM

well here is another solution. kneel on the black plastic cover, drivers side, top of gaurd. When it cracks and breaks, remove it with the intention of replacing it.....then after a month or so, convince yourself its helping vent the engine bay :D

vents cut in side of guard definitly work, left being ideal as it is turbo side.

Remember my wool tuft testing ?
Removing that top of guard cover doesn't work, the flow is really disturbed with most reversing back into the engine bay :(

A NACA duct or louvred cover may work, but a straight open hole doesn't.

Not on a Puma

Doesn't matter as we're trying to remove hot radiator/I-C air anyway.

redrovertdi

7th March 2013, 07:37 AM

I have the guard top vent scoops, heater/fan is dedicated so the driver side rams air into the engine bay but the air cant just flow out, i use a 200tdi left side guard type cover[cut in] and the hot air really does flow out when the thermos are on, as stated earlier i will be putting scoops at the front of the side guards to help move the air, i dont have issues cutting holes in my car as it doesnt have a straight panel on it with 409000ks. My personal opinion is that the body designed back in the late 50s was never designed to conceal a turbo running at 700 odd degrees so a few extra vents can only help reduce engine bay and cabin temps.
Richard

goingbush

7th March 2013, 08:04 AM

D

vents cut in side of guard definitly work, left being ideal as it is turbo side.

the rotation of the air from the fan only makes it worthwhile putting vents on the left side, even if the turbo is on the drivers side.

rick130

7th March 2013, 08:18 AM

the rotation of the air from the fan only makes it worthwhile putting vents on the left side, even if the turbo is on the drivers side.

Air is discharged from an axial fan @ 360*, (and at a tangent, not directly behind, unless ducted)
Exhausting it can be done in any low pressure region, it doesn't matter a jot which direction the fan rotates ;)

uninformed

7th March 2013, 10:22 AM

@Rick, yes I do remember them ;), I was jumping to D thinking you'd pick up A, B and C...but forgetting others here wouldnt be on the same page. In my mind more cold air is possibly going in that top opening, but that will work on mine as now I have an exhast vent.

@goinbush, the big problem with the LR engine bay, especially 300Tdi's is that it is so croweded, ontop of which you have a stacked set of radiators. Air can only move through an area if it has an entry and exit. These have to be matched somewhat. The electric fan on the outside of the A/C condensor is there not only for the A/C but for the engine heat. At speed on the HWY where you would think plenty of air pressure and flow, the air actually dams up inside the engine bay. The Viscous fan not enough to draw it through as there isnt enough exit.

Now I dont have the teck re fans that Rick does, but IMO I cant see the rotation of the fan moving the hot air on the turbo side around the engine and out a vent as efficently as it just passing out a vent on the same side of turbo, pressureisd by forward movement.

Basicly all I have done by cutting the vent is allow the engine bay to have more clean air move through it, taking it off the hotest side. This also helps the airflow through the RAD.

just my opinion (fact may be missing)

uninformed

7th March 2013, 10:24 AM

Not on a Puma

righto, either way dont be shy. If you were closer Id be happy to cut for you.

rainman

7th March 2013, 08:13 PM

So I just got around to finishing my vent off, although I do need to pull it off and paint the mesh (if it ever stops raining here).

I had a piece of security (Crimsafe type) mesh lying around so cut it to basic shape. With Serg's "extra reinforcement" in the back of my mind, and figuring I wasn't going to have much luck putting Nutserts into the mesh, I cut a surround out of some aluminium sheet and installed the M4 aluminium Nutserts. The mesh is sandwiched between the surround and the guard. Total cost - $2.00 for the bolts (I already had everything else)!

https://www.aulro.com/afvb/images/imported/2013/03/946.jpg

https://www.aulro.com/afvb/images/imported/2013/03/947.jpg

https://www.aulro.com/afvb/images/imported/2013/03/948.jpg

Massive thanks to Serg for the inspiration and to everyone for their never ending knowledge. I love this forum ;).

James.

goingbush

7th March 2013, 08:29 PM

i wonder if removing the rubber gasket on the firewall that the bonnet seals on would achieve much, sure bet it would let hot air into the cabin if you opened the vents.

redrovertdi

7th March 2013, 09:05 PM

Ive never had that rubber seal so maybe i should get one...

rick130

8th March 2013, 04:34 AM

i wonder if removing the rubber gasket on the firewall that the bonnet seals on would achieve much, sure bet it would let hot air into the cabin if you opened the vents.

The base of the windscreen is a high pressure area.

All removing the gasket does (or lifting the trailing edge on a conventional bonnet) is allow the air above to flow back down into the engine bay.

flagg

8th March 2013, 06:58 AM

Removing that seal will also increase engine noise a lot. But i have an isuzu so YMMV.

Ancient Mariner

8th March 2013, 07:27 AM

Install a bilge blower 4" 235 CFM $50 from Whitworths:cool:

MacFamily

8th March 2013, 08:08 AM

redrovertdi

8th March 2013, 08:40 AM

Those bonnet side vents are on a mates county, i didnt put them on mine as i figure any hot air coming out would go in my windscreen flap vents[mates county doesnt have the opening vents[yet]]

rick130

8th March 2013, 07:22 PM

While looking for defender related stuff on google last night, I came across this web site, Iam not sure how effective these bonnet vents are, but would have to remove sum of the hot air.

Defender 110 1993 (http://the4x4center.com/b/restoration/defender-110-1993-2)

They're in totally the wrong spot/s to vent radiator air.

I've written this quite a few times now.

Ideally vents need to be in an area of laminar flow or an area of low pressure.
Back near the base of the windscreen is a high pressure zone so if using the top of the bonnet they need to be further forward, ideally not too far behind the radiator.

For inspiration look at where cars that spent time in the windtunnel have their bonnet vents, think Mitsubshi Evo's, etc.

I wouldn't put them there on a pre-TDci Deefer for the reasons redrovertdi stated.

Bush65

9th March 2013, 11:39 AM

redrovertdi

9th March 2013, 12:12 PM

However, when my old V8 rangie had overheating problems was only during low speed off road. Then it would probably have benefited from holes anywhere to let hot air out and there would not have been high pressure at the base of the windscreen. ;)

My 83 range rover had the same symptoms, cure was a later model 4 core radiator and electronic ignition, remember the v8 doesnt have a 700degree turbo in the engine bay.
Richard

rick130

9th March 2013, 02:40 PM

However, when my old V8 rangie had overheating problems was only during low speed off road. Then it would probably have benefited from holes anywhere to let hot air out and there would not have been high pressure at the base of the windscreen. ;)

Just remove the bonnet, problem solved :D

A decent fan could help too :angel:

Luckily you only have oil burners to not worry about these days ;)

goingbush

9th March 2013, 09:12 PM

...., remember the v8 doesnt have a 700degree turbo in the engine bay.
Richard

My V8 Landys were always hotter under the bonnet than my chipped & boosted Td5 is,

I never get that open the bonnet and a heatwave hit you in the face like opening an oven with any of my turbo diesels like I did with my 4.4 or 5.0 V8 Landys

wazza77

12th January 2016, 09:56 PM

Thanks for the useful info rick130, uninformed and rainmain. Running cooler now with the vent done 👌
https://www.aulro.com/afvb/images/imported/2016/01/527.jpg

BadCo.

16th January 2016, 07:12 PM

Looks good wazza! I have just marked mine out, will be cutting both sides tomorrow and I have some black mesh lined up.

BadCo.

17th January 2016, 01:46 PM

Thanks for the inspiration fellas

https://lh3.googleusercontent.com/hipw-Na0RShewy0In0oNrlCEnwyp0GbqrRhF2jtQ1wNS-lvQ6-3DHQp99dTU7bqUiDkoWXFzQl_z3Yhawh_Ei2SinFnmMcL4-8EJTIAvVIAm0QQC1YBYbO3-eximj3IR-i58fF2SI0bpQPmA3OnwZL03Tm-b5om56GkyBuD9zEEyDdaOl9HvskIm_fwou6R627sa-Fjm4bl2OkNvME5_Pqinqy4Bz_CurG-zPR3WKq_JawX1IboTr-vzg4cFFOrqGD_hcyqzopRaLHflHK1IIcB1Vx0cLSLqL07jXqGx wiZ9Y4LX4cxYQkYYd7FSCDOr-UR4jVTbGf36TbzDBsGDdzMtZrtfGCyQ2CK0iqjZlvi_Zfm7-VOMqmk7YnupyxB5xiG0BS5UlDjqg9I65vZ40e9o4tb6ltAzoxg 9AdiuMMnAmO6dVjvRoC_xRCN6nPRmUNsW4AQfbYiebOIWY5N3B ZJ_HUut8PRTOHzcBQzFNfmhuX3h3tQZGD59vyke_-FqTg1tg_OgYcGiPw0cBRG9L1CmQtsZU_5IRXk92UCUXSKGx_nm CjC1O2_DQdV3JGEcJu9M=w1077-h808-no

https://lh3.googleusercontent.com/N9EILlAiH3TpuVHXX9xFEaz740Nv7Vpttaq9QQDve3L9l-dRhw0bbSmVpOMtX8PtjUJgnJyynOm8OsY1Kt6Jy96mLsTFzUNf wIFjbFwl6NWgENSFDbp9srxmtv2uWD9l6k-SwBkatq49GxYNGcg_SR32EPCjsL5S4fbj9HJBg4nzJGsQ5bM_a Ygn-0_F4IFhppbMcveyJMV2hQksR25ZoFeveRVR8EcvmYwNfniqnNJ 916_UoNEytp25o7zxH_51r_Ben9Oh5u0sX5SRC2NxW2W-P9qFByTUTd62PmG5d7V-GX0N052xxN_o_a7TM3erZsaM5yEfPrFrDVN4NwggRZVTZTTlDX MP1PboqG8YttA8_JFqn6iw6HI-UHsHnY-IlydD1iUP9-MQrwqkfzmn3YvSDq5aS8dedA8DJtwzT0VhYGcvrW2icY8Yp9n3 9fBGVd01CD0UVEDXYeGYPV_LDgJSbSu6zUxeka0SaCoWKVAs5N gezpIDxbjYo42y7wm91fRrIDcV7ZP81BuD2S1_I9o7ZRyCRTHD FNJIcboOY7H3yvZ53TdIDg8S82WslMOyR4eJ=w1077-h808-no

There is a TON of heat coming out of that hole!

Baytown

29th January 2017, 11:40 AM

Has anyone any photos of this mod for a Puma?
Thanks.
Ken

Toxic_Avenger

29th January 2017, 03:25 PM

I found a pic: :D
https://www.aulro.com/afvb/images/imported/2017/01/92.jpg

I measured ambient temps of approx 65 Celsius on the hot side of the engine bay in the puma. Details >>here<< (https://www.aulro.com/afvb/90-110-130-defender-county/197704-meet-my-90-share-adventure-12.html#post2633598).
Even heat soak up to 75C reduced to approx 45-50C once the car was underway and there was some airflow. This shows that there is sufficient airflow in the factory design to evacuate engine bay heat.

I don't think underbonnet temps and airflow, on balance, are a huge concern from what I've measured. Remember with the frontal area of a defender, there would have to be a heap of ram-air effect in the radiator area and the ducting which surrounds it.

That being said, any budding scientists should get busy with a simple water manometer (https://en.wikipedia.org/wiki/Pressure_measurement#Liquid_column_.28manometer.29 ) to measure the high and low pressure zones of a defender. Get some data! From what I've read above, the methods employed for testing have been a little subjective ('air feels hot'), and although there would be some correlation between coolant temps and engine bay airflow, there is a few other variables there which might be at play (ambient temps, traffic conditions, vehicle speed, etc) and skewing the results. To play devil's advocate, my measurements may not be telling the full story of what ambient air temps are seen lower in the engine bay (ie directly in the wash of the radiator fan).
For my vehicle, I'd get more data before cutting a stonkin' big hole in the guard.

Water manometer: bit of wood, clear tube, and graduations in mm.
https://www.aulro.com/afvb/images/imported/2017/01/93.jpg
Attach open ends of hose to where you wish to find a pressure differential, read mm graduations from the zero point, and you have a pressure differential in mm H2O (1mm H2O = 9.80665 Pa = 0.0014psi)

rick130

29th January 2017, 09:03 PM

Magnehelic gauges are dirt cheap these days too, we've all gone electronic with pressure measurements, so a Magnhehelic can be had for next to nix.

It's what I was going to use to prove or disprove my theory, moot point now as I think I went for the very last drive in the old girl today....:(

BadCo.

29th January 2017, 10:04 PM

I've got a cheapo indoor/outdoor temp gauge on the intake pipe, so I could probably cover the vents and measure before and after.

Only downside is the intake is on the opposite side of the turbo, so it won't be entirely accurate.

chencq

10th March 2018, 02:09 PM

thanks guys, just done the mod take van out this weekend. looks cool
https://www.aulro.com/afvb/images/imported/2018/03/122.jpg

Ranga

10th March 2018, 08:49 PM

Would a 200tdi guard with the factory outlet on the left be ideal? Bit hard to get though now I'd imagine.

200defenda

11th March 2018, 07:57 AM

It would be cool to modify one of these wolf style air intakes to be a vent 137427 do you guys think it would work the same ?

rick130

11th March 2018, 08:14 AM

Would a 200tdi guard with the factory outlet on the left be ideal? Bit hard to get though now I'd imagine.That's how Serg found how much air could flow from that area as his mates 200Tdi had the stock intake removed and is now just a vent.
As it had no doors he was able to reach out and feel all the hot air pouring out as they drove across a paddock at 40km/h

strangy

11th March 2018, 08:34 AM

The vents are pretty easy to come by.
If you fitted a 200tdi vent,
I don’t think any casual observer would even know it wasn’t factory fitment.
IMO looks a whole better than some offerings, even if not factory recessed into the guard
https://images-na.ssl-images-amazon.com/images/I/71I4nbq%2Bj8L._SX355_.jpg

Ranga

11th March 2018, 08:46 AM

The vents are pretty easy to come by.

Agreed, but if you were to use the whole guard, it would have the recess and remove the need to cut a 300tdi guard[emoji3]

DiscoMick

11th March 2018, 05:35 PM

Why not just put a snow cowl on the fake vent on the top of the mudguard and let the hot air vent out there?
Get one of these for the other side? https://www.aulro.com/afvb/images/imported/2018/03/153.jpg

Tombie

11th March 2018, 08:50 PM

CraigE

11th March 2018, 09:19 PM

I am going to do something similar soon. I am going to use the same as the wing top vent and keep a blank in the car if I need to do a river crossing.

Tombie

11th March 2018, 09:48 PM

What point is the blank [emoji41]

CraigE

11th March 2018, 11:31 PM

What point is the blank [emoji41]
If I need to do a water crossing the vent can be blanked in a couple of minutes, will be looking at putting a vent in the guard lower outside panel, so the need for the blank.
Have the vent and ducted intake for the heater / fan intake and a blank on the other side as have relays in that spot.

Colin

12th March 2018, 07:05 AM

If I need to do a water crossing the vent can be blanked in a couple of minutes, will be looking at putting a vent in the guard lower outside panel, so the need for the blank.
Have the vent and ducted intake for the heater / fan intake and a blank on the other side as have relays in that spot.

But if you blank it for a water crossing how does the water get out?

86mud

12th March 2018, 08:37 AM

The vent on top of the guard is an intake for cabin fresh air.

I did this to my guard 137483

Having this vent has not changed anything during water crossings.

CraigE

12th March 2018, 09:30 AM

But if you blank it for a water crossing how does the water get out?
Same as it does now without one. The plan is to have a blank to stop water ingress into the engine area, obviously would be a wading sheet across the grill as well. I am putting the vent in to allow some of the hot air that builds up around the turbo and exhaust to escape.

Michael2

12th March 2018, 10:28 AM

I used an air intake vent in reverse to make my vent.
I was going to use a LHS guard vent to keep the lines vertical and horizontal, but my supplier was out of stock, so I used the RHS vent, I kept the horizontal line in line with the side indicator / curve ad the slanted look doesn't look too bad.
By having a rear facing vent I theoretically create a low pressure behind it and that helps suck hot air out. I can't test that theory though.
The other aspect I like is that for deep water crossing I can block the hole with some duct tape and maintain my high pressure air bubble against the firewall.

It drops heat build up against the firewall and improves airflow through the radiator and intercooler. On the 300Tdi I think it would work better than on a PUMA as it can wash out exhaust heat by being on the exhaust/turbo side of the engine bay.

I found on a 30.C+ day @ 100kph it drops EGTs by about 50.C

https://www.aulro.com/afvb/images/imported/2018/03/163.jpg

Tombie

12th March 2018, 10:31 AM

Same as it does now without one. The plan is to have a blank to stop water ingress into the engine area, obviously would be a wading sheet across the grill as well. I am putting the vent in to allow some of the hot air that builds up around the turbo and exhaust to escape.

That’s what I’m eluding to..

The vent will allow heat to escape = Tick..

But it won’t have any great effect on creating an “engine bay bubble” when doing water crossings.

The wading sheet will help, but the Defender engine bay gets soaked on deep crossings regardless of any vent in the guard... [emoji41]

CraigE

12th March 2018, 10:35 AM

That’s what I’m eluding to..

The vent will allow heat to escape = Tick..

But it won’t have any great effect on creating an “engine bay bubble” when doing water crossings.

The wading sheet will help, but the Defender engine bay gets soaked on deep crossings regardless of any vent in the guard... [emoji41]
:thumbsup::thumbsup::thumbsup:

DiscoMick

12th March 2018, 12:33 PM

Because the air doesn’t draw out from there... [emoji41]
Yes, I know you've said that before, and I accept it probably doesn't make much difference in normal conditions, since a Defender bonnet is certainly not airtight.
However, in the OPs example, with water rising in the engine bay during a river crossing, I reckon some air would be forced out the top.
Personally, I'd rather take advantage of what is already there rather than start cutting new holes.

Sly

14th May 2018, 09:01 PM

I thought long and hard about the left hand wing vent , weighed up others experience with it done , then made the cut !!.140202

Im not one for making radical changes /mods to the 130 , but this one weighed up .
The motor is new new , larger intercooler and the pdf fuel pump tweeks .Belting up the Hume mid feb at 105kms hr , the egts dipped below 400 and only rose when going up the glenrowan rise.
Then we stuck a new a/c condensor up front , rebuilt the trans case and stuck a O/D out back. The return 700 km plus trip was a 30 deg plus day and with the new gearing temps rose to a constant 500 . Hot air really pushes out the new vent ,on a run out to Charlton Anzac day we measured 85 deg at the vent, 520 egt at 105 kms hr. Used a druk unit remote temp sender attached to the inside of vent grill for engine bay air temps.
Any hot air removed from the engine bay cant be a bad thing .:BigThumb:

DiscoMick

15th May 2018, 08:26 AM

Like these?

Defender guard air vents - Google Search (https://www.google.com.au/search?q=Defender+guard+air+vents&safe=strict&rlz=1C1GCEA_enAU794AU794&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjEwefuq4bbAhXCu7wKHYC4ABkQ_AUICigB&biw=1366&bih=662)

Sly

15th May 2018, 12:01 PM

Yes , a tdi 200 vent cover .

Gav 110

21st May 2019, 05:19 PM

My V8 Landys were always hotter under the bonnet than my chipped & boosted Td5 is,

I never get that open the bonnet and a heatwave hit you in the face like opening an oven with any of my turbo diesels like I did with my 4.4 or 5.0 V8 Landys

Sounds like like it might be worth giving it a go on the old v8 county
After towing a couple of tonne of hay in the middle of summer she gets a bit warm under the bonnet
Ill have to have a look where the AC system sits on the passenger side guard

Any one had a go one (v8 county)?