Hmmmmmmm,

The 90 V8 (Eales 4.5) gets hot - VERY HOT

It gets really really hot when mud plugging in deep sand mud loads of revs and little forward motion, super hot, .......and too hot so something had to be done.

I already have 70% antifreeze, and a BIG 7 row 'supercat' cored larger rad and full cowling & Viscous fan, ...... - but it was not enough

1st step is to get the heat OUT,
when in the mud and goo the undersisde (large area for heat to escape is blocked off, so I have fitted RHS and LHS 'TD' vents, these are intakes, I am using them as "Out" vents :




I have the part numbers for these and the little bushes you'll need to fit, these let out a HUGE amount of heat.

Next was to clear the front end of "Bits on it" ...
this was basically the numberplate (fitted to bonnet now), and the 'marshal' label I have there, a quick measure made me think that these 2 rectangular slabs were blocking more than 1/3 of the front air flow surface area.

then I removed the grill, and the 2 bars :



This then (with a repositioning of the front Hydraulic pipes) - (Erm see drive in last pic ) inc removing the cooler and pipes as not needed - Gave me me an clear area to work on.

A pair of Free 13" Kenlowes sort of sealed the fan options (ta everso Jon W) ....so brackets had to be made up. I did nip into Kenlowe to see what they could offer, -
they had a "Universal fitting kit" - I can tell you right now this is a universal kit - it will universally fit F all .

So armed with some 20x35x2mm angle I fabbed up (read most of a day and a half) a complex but very snug fitting frame :






This was shaped to miss the upper brackets, and also shaped around the Bonnet Slam, lock, .........and the Hyd Hoses ........and PRV on the winch, ..............Hugely time consuming !...

Then where the fans fitted I welded in 5mm bolts so as to have them captive , then the fans (only F Just) slide in and are bolted up into palce.




Jury rigged and tested saw a HUGE movement of air :



A tad of a retrim, number plate onto bonnet and front grill "Just" refits clearing new 2x fans :



Fabrication - takes B ages

Next is the wire it all in Oooer so WVP are getting a call tommorow !

Thought might be of interst, if nothjing else forget Kenlowe fitting kits they offer for a 90 or 110

Nice fans tho

Nige

Very neat install there Nige.

SG

That looks very tidy - hope it sees the end of your overheating problems.

Will that number plate cause you problems with the MOT man? Pretty certain it's strictly speaking illegal, especially with it curved back over the bonnet like that (not easy to read), so probably depends how lenient yours is?

I guess if you do have trouble you might just be able to fit a square plate below one of the headlights?

Thanks for posting the info Nige,, a job i MUST get sorted, and try to get the temp down a bit !!

Neat job Nige, can you turn 2 of the pics showing both ends of the fan frame [it'll make more sense] & locate the number plate either on the bumper end blade [rh side] or above the fairlead [don't reckon it'll cause any problem now] & it'll be fully legal/MOT proof.

Nige, Looks very neat as ever. I had a kenlowe on the lightweight, and it did shift some volume!

I have the number plate on the leading edge of the bonnet too, but to be as compliant as I could, I added a proper one to the light bar:


Would there be any mileage in you adding a numberplate to your roll cage cross bar above the windscreen?

Cheers
Mark

My front numberplate is a sticky-on one and it has been through several MOT's........

Ditto.

Nige, lovely job. I particularly like what you've done with the wing vents. I've also got simerlar 'issues'. First thing I've done is to use an open cored alloy rad (makes a BIG differance). I've also drilled the bonnet and that helped a lot (6 x 2"). However, I still have issues with shifting air from under the bonnet while driving at speed; the engine bay holds heat like you wouldn't believe! My additional plans are to fit an puller fan on top of the bonnet which has been put together by Allisport. I've also got a new exhaust on the way and this should get rid of gas much faster which, I'm hoping, will make a big differance as well as helping performance. The other job I'm going to do is have Allisoprt knock me up a header tank as I'm not a fan of the plastic 'lets split and dump all our water' OME effort. That should also help loose a little extra heat.

You so do- i burnt my hand on the bonnet on saturday!

Okay, ignore me...

Eh ? who said that ?

Nige

Now you've got the side vents, how about using an MGF engine bay fan and under-bonnet temperature sensor to help pull the hot air out of the engine bay??

Or is that OTT?

new one on Ebay

I cant back this up for definate Nige, but a few years back I was having issues cooling a v8 in a series when I happened to say to somebody almost the same thing, I was then told that antifreeze is not as good at cooling than water, he recomended that I just fill with enough anti-freeze to help corrosion and of course adjust accordingly in the winter.

The theory being that antifreeze and summer coolant is just marketing hype.

Cant tell you the result, as I also fitted a new rad etc at the same time, so everything did improve.

Hey Rog,

I was intrigued by this idea so I went out and did some calculations- they are a bit “A-level” and might be wrong as I haven’t done chemistry for a few years.

But lets presume that a range rover cooling system has 8l capacity. To fill it with water would take 8000g of water as the density is 1g/cm3

The molar mass of water is 18 therefore the number of moles of water in a range rover system filled with water would be 8000/18= 444moles

To fill the system with pure ethylene glycol would take 8800g as the density is 10% higher IIRC.

The molar mass of Ethylene glycol is 62 (if I have worked out the chemical composition right- being a carbon chain the two alcohol groups), therefore the number of moles in a range rover system would be 8800/62= 141ish

So we have 444moles of water and only 141moles of antifreeze.

The heat capacity of water is just 75joules/mole which means the closed system can absorb 444*75= 33300 (33.3kj) Joules before the temperature will increase 1 degree.

The heat capacity of ethylene glycol is 150l/mol, but we only have 141moles. In this case the system would absorb 141*150=21150Joules (21.2KJ) per degree heat change.

This shows that water is 50% better at dealing with energy changes than ethylene glycol.

I “hope” I have got everything right above- I have checked my work a couple of times. There a couple of things I don’t know about- in fluid thermodynamics I have no idea If both liquids will absorb and release energy at the same rate (I wouldn’t think they would be different by 50%!) and I have not taken into account the heat capacity changes under temperature and pressure- this may make a difference if you could run the engine at 180degrees as the antifreeze wouldn’t have boiled by that point. I have tried working out the figures at 95degrees but my brain isn’t functioning very well today so I gave up!

It would seem you were told right!

I do wonder if water wetter would have an effect- it reduces surface tension I presume- I wonder if this leads to better contact with the rad cooling fins? Anyone know?

Who’s going to correct my work first I wonder?

F

I only asked a simple Q

Nige

Ill second that....antifreeze is rubbish at getting rid of heat.

The closer you get to pure water the better...there is very little that is better than water for absorbing heat.

Which is completely conflicting info to what I was told in the "MogLite cooling" thread in the International fourm

So what does water wetter do for heat dissipation, and is antifreeze 100% ethylene glycol or does it actually have some stuff in it to do what it says on the tin and help as summer coolant?

i'm going to hold my hands up to this- i think i told youthat you needed antifreeze- i had forgotten that 1 mole of antifreeeze is way bigger than 1 mole of water. Sorry mate.



I would say that there could be some big changes to how antifreeze and water absorb energy under heat and pressure- but i don't believe it would overturn my original calculation.



i am sure that there is someone much more knowledgeable around than me.

i've just done a bit more research and it would seem that my calculations are correct. Water is definitely better than antifreeze.

It would also seem that a good wetting agent would be beneficial- Fairy in your radiator anyone?

Oh Fer Gawds sake.

Please post up detailed instructions of how I get a fairy into my rad.

Do I have to wine and dine him 1st ?

If I rev it over 5500 RPM will he still respect me in the morning ?

Will he get on with both the water mole and the Antifreeze Mole, and if not is that why people fit a water seperator ?

If he brings a friend will that double the cooling ?







Oh Nurse hello, .......my tablets ?

Oh well thankyou

Nige

Hmmmmmmmmm………………. Moglite may be right …………. Anti freeze is not called antifreeze any more ……….. its called ‘all seasons coolant’………..yes, its does the job of stopping the engine freezing but I seem to remember that it has additives to improve cooling when mixed up to 50% ………the additives and water must form a chemical reaction which is why the 50% limit is placed……….more investigation is required me thinks…………. Google is your friend ………. I’ll have a looky see later.

It also has some form a wetter in it ……….. pour some on the ground and then do another patch of just water ………… the coolant patch will takes days to dry, where as the water patch dries within hours………….. tarmac (like my driveway) is a good test for this.


I got moles on my arms and moles in the garden ........... not so sure if I've heard any in the V8 though


Ian

Yes please, what are the part numbers?

I quite like your fan setup too. might replace my mondeo fan if i can find twin kenlowe/spals for less than 1 arm and 1 leg.

I'm busy at the mo ... but just a quick search produced this ....... a GM coolant,

The boiling point at 15psi with up to a 60% mix is impressive ..........




Also take a look at Fuchs oils ............ they all mention either adequate or improved heat transfer at high engine temps...............http://www.fuchstz.com/pageautomotivespecialties.html


Ian

Hey ian,

this looks like a pretty standard ethglycol mix as it's specific density is the same as ethylene glycol.
doesn't really say anything about how effective it is at cooling i don't think.
Can someone with a bit more knowledge please post- i'm a bid out of my depth!

Yes Jim same here …………..

I just find it strange that manufacturers would not go to the effort of making sure that it gave as good cooling as water ………the big names would probably insist on this ……….. its all about big time economics ……… the smaller the cooling system the cheaper the manufacturing cost ……….. if you knock a £1 off each unit and say 1 to 2 million units ……… big money in just one component alone ……..


Ian

Forget the specs - ITS ORANGE

Andy,


PSML

You really are a tart …………….



Ian

erm..............

And its taken you HOW long to work this out

Nige

OK, Nige, I'll take it back to basics with this but have a look here when I'm done:

Basically, moles are an arbitrary measure of the number of molecules; approximately 6.02 x 10[23] molecules per mole.

All the following figures are taken at room temperature and atmospheric pressure; these won't be the same as the values at running temperature but it gives a qualitative idea of what's going on.

Ethylene Glycol (or Ethane-1,2-diol) is a 2 Carbon chain with an alcohol (-OH) functional group on each Carbon. This has a Relative Molecular Mass (RMM) of 62.1 g/mol and a density of 1.114 g/cm3. => One mole occupies 62.1 / 1.114 = 55.7 cm3/mol

This compares to an RMM of 18.0 g/mol and density of 1.00g/cm3 giving a molar volume of 18.0 cm3/mol.

Glycerol has a boiling point of 563.1 K (or 265.1 *C) this compares to water with a boiling point of 100 *C both at atmospheric pressure. Specific heat capacities are 75.2 J/mol K for water and 148.5 J/mol K.

Basically, this means that water holds 75.2 / 18.0 = 4.18 J/cm3 K ie 4.18 Jules of energy are required to raise the temperature of 1 ml of water by 1 *C (Kelvin are use the same scale as *C but start at absolute zero rather than the freezing point of water). For Ethylene Glycol 148.5 / 55.7 = 2.67 J/cm3 K meaning it takes 2.67 Jules to raise the temperature by 1*C. Qualitatively, this means that it'll take more energy to boil Ethylene Glycol BUT V8s don't like running at 200+ *C

I could now go and work out exactly what'll happen in a closed system at around 100*C for a glycol / water mix but most of the important data is in the link and liquids do funny things (like the volume of the mix doesn't equal the volume of the water plus the glycol and the sums for liquid / vapour co-existence are a bit of a PITA and at these temperatures its an important consideration).

As far as the reasons to use Antifreeze go, in the winter that's pretty obvious However, the mixture will also have a higher boiling point than pure water which'll reduce the chance of a boilover when things get warm. However, you don't really want that to be much higher than 120*C (about a 60% glycol mix at atmospheric pressure and about half that at 15 psi). The other advantage of the additives is to reduce the surface tension of the water. Basically, this is what holds drops of water together and this force is reduced by surfactants like fairy. This means bubbles in the cooling system are smaller and the surface contact, on a microscopic level, with the cooling surfaces in the radiator is massively improved. To be honest, though, I don't know whether glycol does this.

HTHs

Have you been stalking that nice physics prof again ?

Basically this is getting silly, seems that antifreeze has some weffect on colling and protect engine from corrosion, by how much I don't know and I am feeling the will to live slipping away....

Where did you copy all that from then ?

Nige

This is a very interesting thread guys kudos to Pugwash and Will.

Yep

Wills good on Google and other search engines

So Will Does pure water vs Water & Abtifreeze mean engine runs hotter with which route ?

Nige

I am certainly no techy on this but as I understand it:

1. You definately need some sort of surfactant to reduce the surface tension of the water, in order that hot clumps of water are dispersed easily so that cooler water can move in. (Mind you a water pump also helps)
Surfactant Good

2. Specific and Latent heat of vaporisation (My O' level Physics now! and this was something I never fully understood) - but the 'coolant' needs to have a high latent heat, it takes/removes a lot of energy to make it boil, which is particularly important where certain parts of the system are very hot (exhaust valves) so causes local boiling of the liquid and draws the heat quickly. Water has a high specific and latent heat than coolants. Water Good

3. What Pugwash said about density of water, (I think thats what he said), denser fluids carry more heat. Water has a lower specific gravity in comparison to coolant. Coolant Good

4. Boiling points. Water has lower boiling point than that of the Gylcols (but Ethyl glycol is much more fun at boiling point!!!) Coolant Good.

In other words water alone is not the best coolant, it definately needs a surfactant and something to stop it boiling over (bit of Glycol).

So who is going to manufacture the "LR4x4 Summer Coolant" and "LR4x4 Antifreeze"? These could be twin bottles for year round protection. Just drain and replace when needed!

Edited to say: Crikey you guys type fast! There are 4 or so posts since I responded!!

All the physical chemistry is making my brain hurt a bit (never did like it much...), but I think in plain English pure water isn't the best solution, neither is pure coolant. Somewhere between these extremes is the optimum mix for cooling. What no-one has managed to figure out - and I'm not even going to attempt it - is what that optimum mix is.

I'd hazard a guess (but guess is all it is) that your 70% mix is too much coolant. If there are lots of complex factors affecting this basic formulae probably aren't going to do more than get us in the right ball park. Has anyone ever done any proper experiments? Presumably the coolant manufacturers have, so what's their advice?

Oi Barker are you listening …… or has the physics lessons driven you to sleep


Reduce the coolant to the LR recommended 50% mix ………… make sure a good 88C stat is fitted and the system is bled properly.

Wire up your new fans ………. take it for a slow off road run, working the engine hard……… the temp should be normally at about 88 – 92C and rise toward the 100C as you work the engine. The fans and cooling system should keep the temp at a 100C or below. Once its got to the 100C ……. Stop and see how quickly it returns to 90 ish …… with the fans running you should be able to watch the gauge gracefully fall .

If all else fails …….hold your bowels and pray to lord …………


To be fair to Will, I think he must have studied chemistry and some of it sunk in ……. because he was also spot on in the hydrocarbons thread …………. I checked up……… what he says makes absolute sense regarding the mixing of water and coolant........... right or wrong........ I dunno, but it seems to fit.


BTW: Tell Mr White to wire your fans from two separate feeds, through 2 separate relays….. this will give you some resilience.


Ian

Surely the short answer is "RTFB" as most antifreeze bottles I have seen quote a level of protection at say 33% concentration, 50% conc and so on. So if the bottle of Acme Quality Antifreeze reckons 33% does to -20 (for example) and you don't live in a place where you expect it to go below that, use that....

Moles are things what burrow in the garden aren't they?

Too much antifreeze is a bad thing and so is none - because it has anti corrosion properties too. In the "good old days" the "good old boys" here could sometimes be found draining their antifreeze out of Series 3's and replacing it with water to "save it for next winter" and as our shop sells antifreeze it always amuses me the rise in sales just before winter appears .... I think a lot of people "stick a bit in just to be sure"

Alternatively the wisdom from RAVE is:

ANTI-FREEZE

PERCENTAGE CONCENTRATION - 50%

PROTECTION - LOWER TEMPERATURE LIMIT

Complete protection
Vehicle may be driven away immediately from cold,
-33° C (-36° F).

Safe limit protection
Coolant in semi-frozen state. Engine may be started
and driven away after warm-up period, -41° C (-42°

Lower protection
Prevents frost damage to cylinder head, block and
radiator. Thaw out before starting engine, -47° C (-53°
F).

CAUTION: Anti-freeze content must never
be allowed to fall below 25% (pre 99MY) or
50% (99MY on) otherwise damage to the
engine is liable to occur. Anti-freeze content
should not exceed 60% (all models) as this will
greatly reduce cooling efficiency.

And from the V8 Discovery 2 manual (this V8 uses the hideously expensive dayglow pink organic acid antifreeze that smells like a pile of dead f@nnies):

The overall anti-freeze concentration should not fall,
by volume, below 50% to ensure that the anti-corrosion
properties of the coolant are maintained.
Anti-freeze concentrations greater than 60% are not
recommended as cooling efficiency will be impaired.

Not sure that adding Fairy Liquid to the cooling system is wise unless you want to look like you rear-ended a Persil tanker when things get hot

HFH & Co

there is a product available from Redline and they call it "Water Wetter" it is reputed to act as an anti corrosion agent and most importantly to lower the engine temperature by 10 to 15 degrees C. I beleive that you can get it from Merlin Motorsport.



Roger

Sorry chaps, I am not much of a chemist, physics was always my thing in school. I have been left behind with all this talk of wetting agents, moles and such - although I do know what they are! I think that you are over analysing.

I know it was a long time ago but can we refer back to this picture?



I presume that this is your heavy duty, extra thick, re-cored radiator? It certainly looks the biz. Just a couple of questions from a simpleton; Is it me or does it appear to have an insulating layer of mud in it? Perhaps it is the colour rendering on my monitor, would not clean black paint offer the best radiating surface type/colour? The other thing that seems to stand out, and again, it could be an interferance pattern from all those verticle lines; are there enough of the little verticle copper fins between the horizontal water channels? They look a little sparse to me, at least when compared to my Tdi rad. I recon that the cooling area of my Tdi rad is, on an area by area basis, about 30% better than that - by memory. If the rad were to be re-cored with the maximum possible surface area rather than the maximum water capacity then it would surely loose more heat - its primary objective.

I know that when Landrover designed the 90 they did some hot climate testing. I presume that this would have involved driving across the Sahara and the like. Now, I know that Nigel's Eales burns alot more fuel than a 3.5 but surely even the standard cooling setup could cope in Britsh autumn temperatures?

One other thing Nige, before you riddle the whole car in vent holes; what about trying the car without the bonnet fitted? If it no longer overheats then I will admit I was wrong and you can get to it with the hole saw.

FWIW, I made no reference to Google in the production of this post.

Chris

Unfortunatly not, Nige. I spend far too much of my time doing this sort of stuff

OK, this is how I see it. Pure water will take a greater ammount of heat per degree of temperature rise so, theoretically, will run cooler but will boil over faster. In practice it won't run cooler, though, due to high surface tension meaning poor heat transfer inside the block and inside the radiator.

For the summer or a garaged vehicle I'd, personally, go for a arround a 25% antifreeze mix with a bottle of 'waterwetter' or simerlar. This should give a good reduction in surface tension, offer corrosion resistance, give a reasonable depression of freezing point and a good, high, boiling point.

If you're leaving you're vehicle outside in the winter or are travelling anywhere chilly I'd push the mix up to about 50-60%. The reduction in heat capacity will be offset by the lower ambient temperature.

My guess is that LR reccomend 50% because its fairly efficient and won't freeze.

Mudplugger, specific heat capacity, as I mentioned above, is basically a measure of how much heat energy is needed to raise a specific mass of a liquid, solid or gas by a degree. Latent heat of vapourisation is baxsically, the enegy required to turn one mole of liquid into one mole of gas at a given temperature. This is not 0 J / mol at 100 *C at 1 atmosphere, though, as the intermolecular bonds (which are VERY strong for a small molecule) still need to be broken. The same is true in reverse; when steam cools to 100 *C it'll loose heat enegrgy without the temperature reducing as the intermolecular bonds reform.

Without wishing to add to the physics, Will's right about the latent heat when boiling / condensing a substance. It takes far less energy to make something boil than it does to make it actually evaporate as steam, and when it condenses down from steam back to liquid it releases this energy. This is why steam burns so much - it's not just water at 100deg, when it condenses on your hand it releases a lot more heat energy than if you dropped water at 99.9deg on your hand.

Who wants to try it?

Surely this would prevent the heat from getting from the cylinder into the water in the first place? 'fraid I am out of other suggestions.

I would personaly go for the larger surface area and find a way to keep it clear. SimonR uses a fine Expamet mesh in front of his radiator as he can remove and clean it easily and it keeps the airborne muck out of the rad. His always seems to be running hot too though.

None of this helps get rid of the hot air generated.

Chris

Expamet mesh

Any links or info

Nige

wot size and how much u want?
i might have some kickin round here

I had to Google for it but: http://www.expandedmetalcompany.co.uk/ Like the fine mesh you find in American style screen doors.

Chris

Just picked up a bottle of antifreeze in the shop downstairs

33% mix protects to -18 deg C
50% mix protects to -36 deg C

How cold is England?

I've seen it drop to -20 several times at night up in Scotland. It doesn't happen very often but you don't want to take the risk. Coming out in the morning to find a cracked block isn't much fun!

True but if it is a one night snap frost there is a degree of thermal inertia involved (if that is the right term) - a couple of hours at -20 will not see the block reach anything like that temperature, whereas two or three days at that temp obviously allows everything to freeze to that temp. Which is why fresh water in my outside water pipe doesn't freeze every time we have a frosty morning, only if it remains below freezing for a day or two.

Or you can just move to a total loss cooling system like on our old Fordson Major on the farm, where you just fill it up every morning, nothing but rainwater in it and its never frozen up yet

It's not pretty but my dad uses fine garden mesh on the front of his RR, same theory as Si that it stops the worst of the gloop from sticking - and so far it's worked really well for the £0 it cost him (nicked from mum's half of the garage )