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Discussion Starter · #1 · (Edited)
My '04 has the one-piece fan and clutch. Replacement from the usual suspects is a bit $$$.

Doing a little research I cam across some alternative solutions, so I dug in, trying to save some money and maybe improve the cooling a bit. Several of the descriptions I read discussed having to trim fan blades, etc, which I didn't want to do. I was able to ascertain that the early 2000's Chevy small truck clutches are dimensionally the same. I found the Imperial 215157 (also private labelled by Carquest, through Advance, under that same number). That clutch is for the non-A/C application. I mated it up with a Dorman 620-602 fan blade. Same application.

The Dorman blade has quite a bit more blade area than the Rover unit. After threading it onto the water pump, I looked closely at the clearance around the shroud. The fitment puts the blade up inside the shroud in the exact position as the Rover fan. There was approx. 3/8" clearance all around. When I popped the top of the shroud cover on, I noticed that the blades almost touched. Eyeballing it, I found that if I pulled the radiator forward, it resolved the clearance issue. I began looking at the rubber mounts but determined that I didn't want to disassemble the whole front end to modify the brackets. Instead, I took the twistlok screws out of the two lower locations where they engage the lower shroud. I took a 1/4" bolt and some fender washers and fashioned a shim. One fender washer on the bottom (had to grind it back a bit to center in the shroud hole) and two on top, then a nut. On top of that I placed another fender washer. Then the shroud goes on, finished with a flat and a nut. Using that combination, I ended up with the same clearance on top as with the bottom shroud.

When I first started the truck it startled me a bit. The new fan is somewhat noisier when cold and very noticeably pulls more air. I wiggled and moved everything around and brake-torqued the truck trying to get the fan to rub. It didn't. I did inadvertently lean on the top shroud and the fan touched, but I'll just refrain from doing that.
 

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Nice piece of engineering. I recently installed a HUD to keep an eye on my temps and, sure enough, she runs hot. So I'm putting in a 180 thermostat this weekend and flushing the system (even tho I've done this recently) and replacing the coolant. What do you think about pulling the fan and disabling the clutch? I mean run bolts through it so it's locked in step with the fan and belt. Maybe there's a more elegant solution but you get my drift. I don't see the point of a viscous clutch when warming up isn't the problem; cooling down is. When has a Disco ever run cold?
 

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Discussion Starter · #3 ·
You would solve one problem but cause several others. That fan clutch operates disengaged the majority of the time. Once you're going 30 or so, your fan is doing little. Engaged, it puts an additional load on the engine which takes fuel to overcome. That load is also borne by the water pump, belt and idlers. In decades past when fans were directly bolted to water pumps, they only lasted a couple years. And they were more robustly constructed. Your water pump is engineered for the anticipated load, which is a small percentage of the time not only circulating water, but driving the fan.

If you have temp issues while you're moving, I'd buy a new radiator- that is, after doing the MotoRad swap. Also, check your aux fan. If it's original, it's likely not working.
 

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Buy a used fan from a 2001-02 D2 and then a 2991 HD clutch from Oreillys. (2991 will either be import direct or hayden) they come with a warranty so replacing it takes little time if you have any probs with the clutch. Breakers usually sell the fan for $30 & the clutch runs $60. Oh and the '02 fan fits the '03-04 cowlings so don't bother with modifying a random fan. This setup works, period, no mods necessary.

Whoever mentioned a flush and 180 stat; get the Prestone backflush kit from the big box parts store. Backflush the heater core while you are doing the engine & radiator. Put a nozzle on your garden hose and spray the radiator from the inside, out - with the fan removed. Start at the top and blast every square inch working your way down & side-to-side. This exercise worked wonders for me. And as somebody else mentioned, check that the aux-fan spins freely and isn't frozen. If this doesn't bring your temps down with a well-functioning Tstat then you could have a faulty radiator. I still run the original so if you are diligent with the flush, you will probably be successful.
 

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Discussion Starter · #5 ·
It's not really a random fan. It's a direct fit. You need six flat washers, two bolts and four nuts to make it work--- and it's $20 cheaper than the approach where you have to track down a used fan blade. best of all, it pulls quite a bit more air, which is nice if you live in New Mexico, like the OP.

As has been written about repeatedly on this and other Rover sites, by the 3rd, 4th or 5th owner, maintenance on these trucks stopped a few guys back. 99% of these D2's have green goo in the cooling systems, since we all know, antifreeze is antifreeze and if it says lifetime, it must be the best. I had one with a cracked tank, so I popped the end off before I tossed it. The tubes were all half-restricted at the openings with corrosion and a grimy gel like substance. It was flowing through the whole unit, but at a reduced rate. The thing is, you don't know what's going on in there, unless you cut it open. If the tstat works, great. If the fan helps, even better. For $200, why screw around? It's probably as old as the car and aside from the corrosion issue, those plastic ends are susceptible to cracking at the water inlet/outlet and especially at the little return tank nipple. It's cheap insurance, especially if you live in a desert.
 

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If you live in a desert area and worried about keeping your motor cool, I am not sure why you would run anti-freeze in your cooling system. It does not cool as well as other non glycol coolants.

I have always ditch the engine fan and run thermo fans. I find they cool better without having to rev the motor to get a good breeze going.
 

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Discussion Starter · #7 ·
Water is certainly more thermodynamically efficient than antifreeze. This allows for more BTU interchange. At the same time, water boils at 212 and 60% mix boils at 230. At 15PSI that extends to over 250.

The Discovery uses the BMW cooling system strategy, which is smaller, lighter components and higher system pressures. Less pressure than BMW, but still, 20PSI. That additional pressure is hard on components, which is one reason they are more failure-prone. I've always joked, there are two kinds of BMW owners, those that change every component in their cooling systems every four years, and fools.

I think alot of Rover owners cook their engines with bad rad caps.
 

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Thanks, guys. As usual, brilliant responses. I use antifreeze because I live at 6000 feet and it gets chilly here. Heat isn't so bad; it was hotter by far in Dallas. Desert doesn't mean hot, just dry.

So here's my strategy for this weekend: oil change first, then drain and Prestone backflush. Spray radiator fins from engine side forward. Install new 180 thermo, refill with 50/50 green and a bottle of Water Wetter. I have checked the aux fan and it still works, but I have my eye on some high CFM fans for when I replace the radiator, which will be this spring. It does run hot even when I'm moving; between 195 and 200. I'll check the fan clutch with the rolled up newspaper trick. I'd replace the fan and rad now if I had them on hand and if I weren't on full Dad duty this weekend (wife's on a girls weekend; I'd like to have a girls weekend too!). I know the radiator's bad and am hoping against hope that the backflush will help. But I'm planning on replacing it.

After this weekend, I'll give a quick update as to how things went. I'm not expecting anything miraculous.

Cheers!
 

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Discussion Starter · #9 ·
By "green" I hope you don't mean the all-purpose, works-in-everything DexCool stuff. Use either Zerex G-05, Peak Global or my favorite, since I buy it in bulk, The BMW grey-bottle. They're made for the all-aluminum engine. I think the Zerex even lists Rover on the label now.
 

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It does run hot even when I'm moving; between 195 and 200.
The earlier D2's had a 192F thermostat. That is, it won't even start to open until this temp. So 195 to 200 is not classed as hot for these vehicles. I believe that you should be putting in a 180 thermostat, all I am saying is that 195 to 200 does not indicate anything wrong with the cooling system.
 

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Discussion Starter · #11 ·
On a hot day I'm sure 225-230 isn't uncommon. That is, if everything is correct on the cooling system. If you have a half-plugged radiator, weak fan clutch and a bad cap, you're on your way to engine damage. The 180 stat does nothing more than provide you a ten degree cushion. Ten degrees gives you an extra 30 seconds or so on a very hot day sitting at a traffic light. At the same time, there's no reason not to run one.

I learned that after two BMW head gaskets- new cap every spring. Same cap on the Rover.
 

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The 180 stat does nothing more than provide you a ten degree cushion. Ten degrees gives you an extra 30 seconds or so on a very hot day sitting at a traffic light.
They have proven that for every degree over around 170F you loose horsepower. So I run my motor cooler (180F thermostat) simply because it runs better, you get more power and you get better fuel economy. Has nothing to do with giving me a 30 second buffer.

Also one of the first things I do is disconnect the throttle body heater so that I get cooler air into the motor.

A final point is that if you want the most warning that your motor is getting hot, don't run glycol based coolants. The coolant is there to keep the metal parts of your motor from getting too hot. Glycol pulls the heat out of the motor at a relatively slow rate. Therefore, your motor is getting a lot hotter than that being reflected in the coolant temp. By the time the coolant temp shows that it has overheated, you have probably already done the damage to the motor. Even though Glycol may boil at a higher temp, it actually turns to steam at a lot lower temp. It is a alcohol based substance.
 

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Discussion Starter · #13 ·
Even if that temperature was ideal for this particular engine, the power difference would be undetectable. I have played with op temps on the dyno over the years and some engines do make less or more power at different temps- it depend son the engine. But none over about 1% inside of preignition boundaries.

There have been several billion vehicles engineered by their respective manufacturers to run on ethylene glycol based coolants. Huge sums of money and vast amounts of time have been invested into the development and application of this technology, and its been proven in practice- for example, three and a half quadrillion miles in the US alone just last year. It is far from a flawed principle. The issue with thermal conductivity and the difference in specific heat between water and glycol is far offset by the latter's higher boiling point.

I am completely lost on the statements about glycol. I agree that glycol is less thermally conductive that water. But the design of the cooling system accommodates for that. And since glycol transitions from liquid to vapor phase at just shy of 400 degrees, it will continue to function long after the engine running on water has overheated. (that is subject to the dilutionary effect). Glycol turning to steam- this is basic physics. Matter exists in four states, solid, liquid, gaseous and plasma. Water and the glycol compound are soluble in each other, so they no longer act independently. Even so, if you ran a 100% glycol compound, it isn't going to transition from a solid state to a vapor state at any other point than its transitional temperature, which is its boiling point. And alcohol based? While true, it's misleading. Ethylene and propylene glycol are members of the alcohol family, but when you say "alcohol", people think of ethanol or methanol. They're all just members of the same hydroxyl functional group. Comparing methanol or ethanol to ethylene or proylene glycol is like comparing graphite to diamonds.

If your truck is overheating in normal operation, your problem is a failing inside of your cooling system. If you rock crawl in the desert- or pull heavy trailers over mountains, you may need to get a 4-core radiator. Or even better, install an engine oil cooler. If the Rover does have one Achilles's heel, it's the grille- it's very stylish, but obstructs airflow while sitting or moving slowly.
 

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Even if that temperature was ideal for this particular engine, the power difference would be undetectable. I have played with op temps on the dyno over the years and some engines do make less or more power at different temps- it depend son the engine. But none over about 1% inside of preignition boundaries.
I am sure that you will be able to find your usual posts on forums that support your view. So I am not going to debate this with you.
For those that want the truth, obtain the book "how to power tune rover V8 engines" by Des Hammill. Go to page 197 and it states that the maximum power is developed in any engine at 175F. By the time it gets to 212F it would have lost 10% of its horsepower. Such statements are backed up by many technical references on the internet. I do not know about you, but people spend big money to get an extra 10% in HP. To obtain by just swapping a cheap thermostat is a no-brainer.



There have been several billion vehicles engineered by their respective manufacturers to run on ethylene glycol based coolants. Huge sums of money and vast amounts of time have been invested into the development and application of this technology, and its been proven in practice- for example, three and a half quadrillion miles in the US alone just last year. It is far from a flawed principle. The issue with thermal conductivity and the difference in specific heat between water and glycol is far offset by the latter's higher boiling point.
How is its ability to transfer heat from you engine has anything to do with boiling point. Water will transfer heat from the engine to the coolant nearly 3 times faster than Glycol. So as your cylinders heat up under load, water based coolants will cool it down 3 times quicker compared to Glycol. This is a scientific fact and you will not be able to argue this one from anything on the internet, except maybe posts from forums.


I am completely lost on the statements about glycol. I agree that glycol is less thermally conductive that water. But the design of the cooling system accommodates for that. And since glycol transitions from liquid to vapor phase at just shy of 400 degrees, it will continue to function long after the engine running on water has overheated. (that is subject to the dilutionary effect). Glycol turning to steam- this is basic physics. Matter exists in four states, solid, liquid, gaseous and plasma. Water and the glycol compound are soluble in each other, so they no longer act independently. Even so, if you ran a 100% glycol compound, it isn't going to transition from a solid state to a vapor state at any other point than its transitional temperature, which is its boiling point. And alcohol based? While true, it's misleading. Ethylene and propylene glycol are members of the alcohol family, but when you say "alcohol", people think of ethanol or methanol. They're all just members of the same hydroxyl functional group. Comparing methanol or ethanol to ethylene or proylene glycol is like comparing graphite to diamonds.

If your truck is overheating in normal operation, your problem is a failing inside of your cooling system. If you rock crawl in the desert- or pull heavy trailers over mountains, you may need to get a 4-core radiator. Or even better, install an engine oil cooler. If the Rover does have one Achilles's heel, it's the grille- it's very stylish, but obstructs airflow while sitting or moving slowly.
I suggest that you recheck the vaporisation temps of Glycol again. It is nothing like 400 degrees. It is far less than water. Vaporisation temps have nothing to do with boiling temps. Everyone knows that alcohol evaporates at a relatively low temp. Glycol is alcohol based.

I have not suggested that overheating is not related to a poor cooling system. What I have said is that you will not know about it by monitoring the temp of a Glycol based system until later. This is because it takes a lot longer for that extreme heat in the cylinders and other components to transfer to the coolant.

If there are any geeks out there that really want to get into the scientific stuff, read this http://www.doiserbia.nb.rs/img/doi/0354-9836/2015 OnLine-First/0354-98361500213S.pdf
 

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Discussion Starter · #15 ·
I hate to beat up on you as you are very knowledgeable about the various mechanical aspects of these vehicles and your contributions on these topics are valuable to the membership here. But for some reason you keep wading in over your head when the topic moves past mechanics and goes towards sciences. Engineering is the science of applying other scientific principles in physical applications. The underlying science is physics. If you don't have a clear understanding of those fundamentals, understanding the whole picture isn't possible.

To tackle your first one, the Rover engine is a pretty basic pushrod V-8 passenger car engine. It is far, far away from pushing any sort of performance envelope. Internal operating temperatures become a concern when engines are pushed close to their physical limitations. If we were talking about a 12.5:1 compression engine turning 8,600RPM, I would have concern about combustion chamber hot spots due to the rather crude way the Rover circulates water. I'm guessing I would begin to see the effects of preignition from spots on the downflow sides of the combustion chambers. Despite your suggestion, I won't need to Google this. I have had quite a few engines on our dynamometer and I have plenty of experience in this. With the Rover, there's nothing that comes within miles of causing the effects you have conjured. The Rover has one factor that, all by itself, removes these effects from the equation- aluminum heads. The thermal transfer properties of aluminum are such that what you suggest simply can't occur. Gaining 22 horsepower with a 10 degree bump in cooling system temperatures simply defies all the principles of thermodynamics.

To answer your second question, water has the ability to transfer heat better. However it boils at a lower temperature. Once the water boils, it loses its ability to transfer heat. Removing heat rapidly works great until you hit the wall where water boils into steam and stops working altogether. Adding a substance such as ethylene glycol reduces the systems ability to remove heat, but allows it to do it at higher temperatures. In short, water works awesomely until it hit the wall where it doesn't any longer. It doesn't matter how well it works once it meets that failure pointg Chemical coolants allow the system to continue to work far beyond that failure point. And the information you offer on glycol is miles away from being correct. You propound that glycol has 300% less ability to transfer heat than water, which is incorrect. A 50/50 mix of glycol and water has about a 20% deficit over water. You need to learn about a concept in physics called "specific heat" before fabricating statements and offering them here as fact. This is a site that i regularly recommend to people that need to understand an engineering concept. It has quite a bit of practical information on a huge volume of practical topics. i was pleased to see that someone already did the legwork on this: Ethylene Glycol Heat-Transfer Fluid

Your third section starts with "vaporization temps", which really isn't a thing. Vaporization is a generic term that describes what happens when a substance in its liquid phase either evaporates or boils. I don't have either the time or desire to explain the kinetic theory of gases or how evaporation works on a molecular level, but the basics are these: evaporation can only occur where no equilibrium exists. If I pour a saucer full of ethanol tonight and leave it on my desk, it won't be there in the morning. That's because it had somewhere to go, and ethyl alcohol has a high volatility. If I leave it in the bottle, it won't. If I do the same with cooking oil, I'll have a different result because that substance is less volatile. This volatility is measured by vapor pressure. In order for the fluids in a cooling system to "vaporize" they need to either boil or they need to evaporate. Neither can happen in a closed cooling system prior to exceeding the boil temp of the coolant.

Your assertion that your engine is overheated long before the temperature sensor can read the true temp is just silly.

You seem to keep hanging on to this "glycol is an alcohol" thing. I would think that anyone that's ever spilled antifreeze on their shop floor or their driveway would recall how it just laid there. But to put it to rest, Glycol is a member of the alcohol family and is relative to ethanol, as an elephant as a mammal is the same as a dolphin, or that the metal titanium is the same as lead.

Compare the vapor pressures of some common substances for yourself:

Acetone 30
Allyl alcohol 2.3
Allyl chloride 40
Aluminum nitrate, 10% solution in water 2.4
Aluminum sulphate, 10% solution in water 2.4
Amyl acetate 0.47
Aniline 0.09
Beer 2.4
Benzene 14
Benzyl alcohol 0.013
Bromine 28
Butyl acetate 1.5
Butyl alcohol, 1-butanol 0.93
Butyric acid n 48
Calcium chloride, 25% solution in water 2.4
Calcium chloride, 5% solution in water 2.4
Carbon disulphide 48
Carbon tetrachloride 15.3
Chloroform 26
Cyclohexanol 0.9
Cyclohexanone 0.67
Ethyl acetate 14
Ethyl alcohol 12.4
Ethyl glycol 0.7
Ethylene glycol 0.007
Formic acid 5.7
Furfurol, 2-Furaldehyde 0.3
Heptane 6
Hexane 17.6
Isopropyl alcohol (rubbing alcohol) 4.4
Kerosene 0.7
Methyl acetate 28.8
Methyl alcohol, methanol 16.9
Methylene chloride, dichloromethane 58
Milk 2.4
Nitrobenzene 0.03
Nonane 0.6
Octane 1.9
Pentane 58
Phenol 0.05
Propanol 2.8
Propionic acid 0.47
Sea water 2.4
Sodium chloride, 25% solution in water 2.4
Sodium hydroxide, 20% solution in water 2.4
Sodium hydroxide, 30% solution in water 2.4
Styrene 0.85
Tetrachloroethane 0.7
Tetrachloroethylene 2.5
Toluene 3.8
Trichloroethylene 9.2
Water 2.4
 

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I hate to beat up on you ..... blah.. blah But for some reason you keep wading in over your head when the topic moves past mechanics and goes towards sciences.
I completely understand the topic. I have done my research and experiments.



To tackle your first one, the Rover engine is a pretty basic pushrod V-8 passenger car engine. It is far, far away from pushing any sort of performance envelope. Internal operating temperatures become a concern when engines are pushed close to their physical limitations. If we were talking about a 12.5:1 compression engine turning 8,600RPM, I would have concern about combustion chamber hot spots due to the rather crude way the Rover circulates water. I'm guessing I would begin to see the effects of preignition from spots on the downflow sides of the combustion chambers. Despite your suggestion, I won't need to Google this. I have had quite a few engines on our dynamometer and I have plenty of experience in this. With the Rover, there's nothing that comes within miles of causing the effects you have conjured. The Rover has one factor that, all by itself, removes these effects from the equation- aluminum heads. The thermal transfer properties of aluminum are such that what you suggest simply can't occur. Gaining 22 horsepower with a 10 degree bump in cooling system temperatures simply defies all the principles of thermodynamics.

To answer your second question, water has the ability to transfer heat better. However it boils at a lower temperature. Once the water boils, it loses its ability to transfer heat. Removing heat rapidly works great until you hit the wall where water boils into steam and stops working altogether. Adding a substance such as ethylene glycol reduces the systems ability to remove heat, but allows it to do it at higher temperatures. In short, water works awesomely until it hit the wall where it doesn't any longer. It doesn't matter how well it works once it meets that failure pointg Chemical coolants allow the system to continue to work far beyond that failure point. And the information you offer on glycol is miles away from being correct. You propound that glycol has 300% less ability to transfer heat than water, which is incorrect. A 50/50 mix of glycol and water has about a 20% deficit over water. You need to learn about a concept in physics called "specific heat" before fabricating statements and offering them here as fact. This is a site that i regularly recommend to people that need to understand an engineering concept. It has quite a bit of practical information on a huge volume of practical topics. i was pleased to see that someone already did the legwork on this: Ethylene Glycol Heat-Transfer Fluid
Again you show no understanding of what you are talking about. You NEVER supply any references to back up what you say.
This table gives you how much heat is required to turn the liquid to vapour. Fluids - Latent Heat of Evaporation You will note that it takes 3 times more heat to turn water to vapour than Glycol. You will note that it is from the same site as you used as a reference. You are correct in stating that steam does not cool.
I provided the technical article already that went into all the aspects you mentioned.

Your assertion that your engine is overheated long before the temperature sensor can read the true temp is just silly.
Again you argue against yourself. You admit that it takes a lot longer to transfer heat to glycol compared to water. So once the metal part of your engine gets to a critical heat, it will take a lot longer for that heat to transfer to the glycol. Therefore, the heat in the block will take a lot longer to show up in the coolant temp.

I will give you a practical example. I have run the same temp gauge when I was running a 50/50 Glycol coolant and now that I use a non-glycol race coolant. As with any engine, as I work the motor up a hill, more HP is required, which in turn generates a lot more heat. Going up the same hills, the temp gauge use to barely move with the glycol mix. With the race coolant it will increase very noticeably. That is because the water based race coolant is actually sucking the heat out of the engine and keeping the block temps a lot cooler than with glycol that could barely remove any of the heat from the block. Allowing the block to get to very high temps is going to cause damage. The water based coolant will suck the heat out before it gets to these high temps. The Glycol will not. But you will not know from the temp gauge because the heat is not being transferred properly into the coolant temp.

CT090. I know that you like to think you are the expert in everything, but in this case, like most others, it is well outside you level of understanding.
 

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Discussion Starter · #17 ·
You clearly lack even the basic, fundamental understanding of physics and your reluctance to admit this prevents us from having any sort of meaningful debate. You aren't even grasping what i am writing about, and your reference to latent heat is a good example. Where exactly are we looking to convert the contents of our cooling systems from fluid to vapor?

The problem here isn't that you're wrong, it's that you don't even know what you don't know. You wouldn't know what wrong is because you don't know the correct answer to begin with. You're an ancient Greek that believes that the sun and moon and constellations govern all that's around you because once, on a full moon, a wolf ate your goat and the moon must have caused it.

You're a guy that has repaired some cars and trucks over the years and believes that experience translates to an understanding of the engineering principles behind what you're repairing. At least you've gotten off of the antifreeze is alcohol thing.
 

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You clearly lack even the basic, fundamental understanding of physics and your reluctance to admit this prevents us from having any sort of meaningful debate. You aren't even grasping what i am writing about, and your reference to latent heat is a good example. Where exactly are we looking to convert the contents of our cooling systems from fluid to vapor?

The problem here isn't that you're wrong, it's that you don't even know what you don't know. You wouldn't know what wrong is because you don't know the correct answer to begin with. You're an ancient Greek that believes that the sun and moon and constellations govern all that's around you because once, on a full moon, a wolf ate your goat and the moon must have caused it.

You're a guy that has repaired some cars and trucks over the years and believes that experience translates to an understanding of the engineering principles behind what you're repairing. At least you've gotten off of the antifreeze is alcohol thing.
Again and again, just words with nothing to back them up.
You often talk about how you build high performance/high tech engines. If the difference between head temperatures and coolant temperatures are not an issue, why are so many modern ECUs using head temp sensors that bypass the cooling system and measure directly the heat of the metal.

However, due to being an expert in physics etc, you will enjoy this article that goes into the heat transfer rates, head temps in various positions, flow rates, coolant types, etc, etc http://naca.central.cranfield.ac.uk/reports/1949/naca-report-931.pdf
 

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Interesting debate going on between you two. Can definitely tell I'm on a land rover forum. If this was ford truck forum you two would've started the name calling a long time ago. I love how each of you will acknowledge the other is correct about one thing and still argue the validity. Lol, good stuff. Can't wait to work on my cooling system once the beast gets running. Will be reading "how to power tune rover V8 engines" by Des Hammill in the meantime.
 

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Discussion Starter · #20 ·
Once again, obfuscation.

I'm not going to blindly read a 75 year old, 25 page study that may or not contain some point that you're trying to make, but don't even bother to assert here.

Lets go back to your last point about latent heat. Since you clearly have no comprehension of the principles behind it, I'll explain them. Then you can explain to all of us how they relate to this discussion and how the data you provided proves any particular point you are trying to make.



As stated before, matter four states, or phases. Those are solid, liquid, gaseous and plasma. Substances transition from one to another at a particular temperature. In our example of water, it becomes a solid at 32F and a vapor at 212F. These temps assume sea level atmospheric pressure. There is no such thing as 213 degree liquid water unless you increase atmospheric pressure.

The citation you offered discusses how much total energy it would take to cause a defined quantity of a substance to transition from its liquid state to its gas state. Now, we discussed previously that water changes state at 212 degrees. For reference, ethylene glycol changes state from liquid to vapor at 386 degrees.

What would be very helpful to all reading this discussion would be for you to explain what this has to do with the ability of either of these materials to conduct heat.

For some reason you are hung up on evaporation/vaporization/boiling and think this has something to do with the topic. First off, the object of a cooling system IS TO NOT BOIL. Second, your obsession with e/v/b is preventing you from looking at the actual physics that apply, which is thermal conductivity. This is a very basic concept, and it speaks to exactly what it says- the conduction (transfer) of thermal energy. Engine makes heat. Heat is conducted from the metal structure of the engine to a cooling fluid. Fluid is pumped from engine to heat exchanger (radiator). Heat exchanger facilitates transfer of heat energy outside of closed cooling system and into another media (atmospheric air). Thermal (heat) conduction (transfer). This same principle of thermal conductivity applies to your temperature sensor. But this is what you're missing- the cooling fluid isn't conducting heat. It's is already at temperature, so the sensor is reading the temperature of the coolant. What we are now talking about is thermal diffusifity, which is how fast thermal energy will pass through a particular material. But what does that mean in real-world applications? Nothing. The gauge on your dash moves much more slowly than the system is reading. The sensor in the block changes output at a much slower rate than the change in temperature acting on it. And unless you're watching the gauge at all times, then none of this matters.
 
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