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I'm pretty sure you are allowed to take the cooling fan off for the mpg test. 

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2 hours ago, Snagger said:

I'm sure it's possible to have multi-speed electric fans, but it'd probably not be cheap to incorporate such a controller.

Freelander has that as standard. I've got the (very simple relay based) unit waiting to wire into my trucks, which both currently have twin fans controlled by the ECU. You can do "one fan, two fans" or you can do "both fans in series, both fans in parallel" which is the LR FL way & nice and quiet.

Also, Saab definitely have similar as I've had at least two Saab fan setups on other trucks with a limiting resistor pack to drop the fan speed, much like heater blower resistor packs but much bigger. Not sure about others but can't believe LR and Saab are alone.

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47 minutes ago, mad_pete said:

I'm pretty sure you are allowed to take the cooling fan off for the mpg test. 

I don't know the rules, but that'd be appalling cheating.

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9 minutes ago, FridgeFreezer said:

Freelander has that as standard. I've got the (very simple relay based) unit waiting to wire into my trucks, which both currently have twin fans controlled by the ECU. You can do "one fan, two fans" or you can do "both fans in series, both fans in parallel" which is the LR FL way & nice and quiet.

Also, Saab definitely have similar as I've had at least two Saab fan setups on other trucks with a limiting resistor pack to drop the fan speed, much like heater blower resistor packs but much bigger. Not sure about others but can't believe LR and Saab are alone.

The X-Fan setup uses a two-level thermostatic switch that allows one fan to come on at one temperature, and a second fan (or system of fans) to activate at a higher temperature.  The trouble is that this means that the engine temperature has already climbed higher than it should for the second fan to be activated.  An rpm responsive fan would keep the temperature more even. 

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12 hours ago, FridgeFreezer said:

Freelander has that as standard. I've got the (very simple relay based) unit waiting to wire into my trucks, which both currently have twin fans controlled by the ECU. You can do "one fan, two fans" or you can do "both fans in series, both fans in parallel" which is the LR FL way & nice and quiet.

Also, Saab definitely have similar as I've had at least two Saab fan setups on other trucks with a limiting resistor pack to drop the fan speed, much like heater blower resistor packs but much bigger. Not sure about others but can't believe LR and Saab are alone.

It that the wiring diagram found on the internet when you search for Tridon TFS 214? Such as: http://www.ichi-intl.com.au/Personal/XJ6 SI/XJ6 SI.htm ? 

I had a version of that for quite a while, (but with no aircon or electric water pump), and it worked well. It seems to have been used by quite a few people out there. I pulled it all out, though, because when I was doing some highway runs at about 30c and above the fans would come on at low speed and then never speed up or switch off. Very annoying. In a milder climate it would be very good. 

I never tried any of the complicated controllers you can buy from places like Summit because none of the reviews were too good, and they would be a real weak point anyway. Now I've just got a temperature switch and two big relays for the two fans, which are EL Falcon fans in their own shroud. This also meant I could remove the two little fans for the aircon condensor, which I would think improves the airflow. Unfortunately, real testing will have to wait since it's cooled down for "winter" and only 35c during the day! 

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My BMW road diesel has a proportional speed control, its trivial to design a reliable speed control and equally trivial to determine that the motor is turning, drawing appropriate current and apply appropriate circuit protection. Unfortunately both electric fans and mechanical fans get bad reputations due to bad implementation, often by DIY bodges and failures to maintain. I've had people tell me Kenlowe fans are rubbish, when I look at the rats nest of Scotchloks and tyraps holding them together I can see why they would make that conclusion. I've seen DIY V8 conversions where the state of tune was so bad and air flow was so compromised the engine fan had zero chance of cooling the system.. rubbish these electric fans! 

Analyse your application carefully, design and implement appropriately and  either mechanical or electrical will be perfectly fine and reliable.

On the old 70's era Peugeot in line four, a magnetic clutch was used to engage the engine fan. French electrics were never fantastic, probably on a par with Lucas but I remember that fan setup being very reliable.

 

 

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Trivial??? I had enough trouble figuring out what did what with that relay-based design I mentioned above! 

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1 hour ago, Davo said:

 

I had a version of that for quite a while, (but with no aircon or electric water pump), and it worked well. It seems to have been used by quite a few people out there. I pulled it all out, though, because when I was doing some highway runs at about 30c and above the fans would come on at low speed and then never speed up or switch off. Very annoying. In a milder climate it would be very good. 

 

Ok I'll bite and ask the same question to you, why does your electric fans running mean you don't trust them or are annoying? Did it overheat?

Actually, thermally cycling the radiator by rapidly cooling and then rapidly heating it back up is probably far worse than maintaining a constant water temperature.

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5 minutes ago, Davo said:

Trivial??? I had enough trouble figuring out what did what with that relay-based design I mentioned above! 

I know, I didn't mean to infer that the design is necessarily in the realms of every DIY installer, to clarify what I meant - a proportional fan controller as discussed previously isn't hard to design and some major manufacturers do choose to do so.

Also an after market setup for the DIY installer should be no more complex to fit than a bi-metal switch setup that many are familiar with.

With some engine setups, particularly conversions there isn't much choice about the type of setup to use, in some climates and usage the choice is largely irrelevant ( for example TDi's in the UK )

I had some time investigating cooling fans on site generators, the generators were failing due to overheating. Diagnostics reported inadequate air flow. The manufacturer stated that the generators were being worked close to their design limit and that the customer should fit the more expensive, more reliable and generally better electric colloing fan upgrade. That made little difference to the reliability so I was asked to look into it. The first one I visited took me two hours to dig out, it was under 2m of snow. It showed that looking at the application and design is more important than the actual technology used.

 

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Posted (edited)
14 minutes ago, Bowie69 said:

Ok I'll bite and ask the same question to you, why does your electric fans running mean you don't trust them or are annoying? Did it overheat?

Actually, thermally cycling the radiator by rapidly cooling and then rapidly heating it back up is probably far worse than maintaining a constant water temperature.

Because they weren't supposed to be running all the time like those pesky engine-driven fans, using up valuable electricity. That's one of the best things, the way they switch on, do their job, and then go away until the next time. 

The high and low temperatures aren't far enough apart to do anything, so the cycling isn't a worry. 

Edit: Actually, with the engine-driven fan, the temperatures were far more extreme - too cool in cool weather, too hot during hot weather idle, hence my latest electric fan experiment. 

Edited by Davo
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9 minutes ago, GW8IZR said:

I know, I didn't mean to infer that the design is necessarily in the realms of every DIY installer, to clarify what I meant - a proportional fan controller as discussed previously isn't hard to design and some major manufacturers do choose to do so.

Also an after market setup for the DIY installer should be no more complex to fit than a bi-metal switch setup that many are familiar with.

With some engine setups, particularly conversions there isn't much choice about the type of setup to use, in some climates and usage the choice is largely irrelevant ( for example TDi's in the UK )

I had some time investigating cooling fans on site generators, the generators were failing due to overheating. Diagnostics reported inadequate air flow. The manufacturer stated that the generators were being worked close to their design limit and that the customer should fit the more expensive, more reliable and generally better electric colloing fan upgrade. That made little difference to the reliability so I was asked to look into it. The first one I visited took me two hours to dig out, it was under 2m of snow. It showed that looking at the application and design is more important than the actual technology used.

 

Ah, okay. Yes, pretty much every controller I looked at had some reliability problem, (based on reviews), or bad manufacturer support, so I've got the cheap-and-simple DIY system. 

Nice example, too! So for me, I live in a very hot climate, my application is pretty extreme, and so far electric fans work better. Time will tell. 

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6 minutes ago, Davo said:

Because they weren't supposed to be running all the time like those pesky engine-driven fans, using up valuable electricity. That's one of the best things, the way they switch on, do their job, and then go away until the next time. 

The high and low temperatures aren't far enough apart to do anything, so the cycling isn't a worry. 

Edit: Actually, with the engine-driven fan, the temperatures were far more extreme - too cool in cool weather, too hot during hot weather idle, hence my latest electric fan experiment. 

Hmmm, I sort of see your point, but I still come back to the fact that your engine needed cooling, and the system used as little energy as possible (for an electric fan) to do the job, I'm at a loss as to why you see this as an issue, but there we are :)

You don't tend to hear viscous fans locking up while driving, but I bet they do :)

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At highway speeds, the things aren't supposed to run, (much, at least), but it was in hot weather. However, I should have mentioned that at the time I didn't realise how important the low-pressure side of the airflow was and didn't have that set up at all. I'm working on that now to see if it helps with this latest version. Airflow into a Range Rover radiator is pretty bad, and out again into that crowded engine bay is pretty bad, so eventually it dawned on me that in order for these electric fans to work as well as possible I'd have to improve this. 

Something else I forgot to mention is that they are far superior at idle in removing that "pillow" of hot air Range Rovers get under their bonnets, which is a really big deal in a place like this. It seems to be a feature unique to Rangies and their bonnet shape. 

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15 hours ago, Snagger said:

The trouble is that this means that the engine temperature has already climbed higher than it should

Not true, that just means you've got the wrong temperature range of switch. In the Megasquirt I can set them to be 1deg apart if I want, and if the 2nd one comes on it is set to then stay on until BOTH go off again. It'd be easily done with a very simple circuit & a standard temperature sender if you don't have an ECU to do it.

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Ok that took a good half hour! :D

Some thread lads, learned a lot, baffled by a lot more. I only have one thing to add and it's been hit upon - the over engineering in LR cooling systems. I know I've mentioned it before, and you'll see it when I get my early RR into the series, but I had to cut my (Td5) viscous fan down by 3" to each blade and mount it without a cowl because of an oversight when I was measuring to mount the engine. Not sure how I'm going to sort it actually. Might have to go leccy.

Anyway I've sat for two hours in 35deg Athenian car park-esque traffic absolutely bricking it that a head gasket blow was imminent, up and down Peloponnesian mountains in baking heat, and in 40k miles this Td5 has been bullet proof temp wise. Ok I'll admit I think my viscous unit may have been semi seized from the start. The early RR big open grill must help too, and whereas I made up small panels to close the gaps left between the Defender/Disco rad ends and the RR inner body work, I never fitted them so there's def a some ram flow into the bay itself when moving. Prob all worthless info but anyway great thread for when I do need to make a prettier setup in the RR rebuild. Cheers!

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31 minutes ago, Shackleton said:

 

Some thread lads, learned a lot, baffled by a lot more. I only have one thing to add and it's been hit upon - the over engineering in LR cooling systems. 

 

That is one certainty, but I suspect you could apply it to any manufacturer if you live in the UK, or in fact anywhere that it isn't regularly 50C -all vehicles will need to be designed to cope with this, I mean if you bought a car in the UK and drove it to,say, Morocco, you would expect it to keep working, no?

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29 minutes ago, Bowie69 said:

That is one certainty, but I suspect you could apply it to any manufacturer if you live in the UK, or in fact anywhere that it isn't regularly 50C -all vehicles will need to be designed to cope with this, I mean if you bought a car in the UK and drove it to,say, Morocco, you would expect it to keep working, no?

 

Absolutely right, and if I modified a car ( anything really ) to make it better for a particular environment or for a particular task  I wouldn't necessarily expect it to work if I decided to use it in a different  environment or for a different task. Not without revisiting the modification to see if the criteria were still OK..

I probably wouldn't drive a car set up for winter UK green laning (or more realistically a typical weekend pay and play shed) to Morocco without giving the MT tyre selection a second look - whereas in reality a stock Defender straight from the dealers would do both jobs :-)

 

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British cooling systems have long been regarded as suspect in really hot climates and I often think of the "tropicalisation" needed for Spitfires when I'm doing something similar with my Range Rover. There's an interesting point from an interview with one of the Range Rover engineers where he said that to test the car in a hot climate they took it to the middle east somewhere, drove it hard, and then parked it out of the wind and let it idle. They found it wouldn't cool down and eventually realised that they needed to seal the radiator to the body with rubber strips. It sounds like it was a new idea for the time! However, apparently that still wasn't enough, which is why they later had a "Tropicore" radiator available for models with air conditioning. Adding aircon really brought out the limitations of the cooling system, or, more accurately, the limits of the engine bay ventilation. Which is why, like many people over the decades, I've been modifying the car to try and improve this. It's pretty good up to about 35c, (which would be a heatwave for Europe), so it would be acceptable for most of the northern hemisphere, but over here that is a common winter afternoon temperature and it's above that when these cars tend to struggle and the limitations of a viscous fan tend to show up. 

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"Heat Wave for Europe" - Maybe change that to Northern Europe and Scandinavia. Large parts of Russia, Southern Europe, The Balkans and The Peloponnese regularly get higher average temperatures.

Slightly O/T (Lord Forbid) but still on cooling. One of the mods we've fitted in the past, to vehicles going to Southern Europe, North Africa etc., if known to suffer from a less than adequate cooling system is the old VM 2.4/2.5 TD rad. I allows the fitting of a standard intercooler but is wider than a Tdi rad. It's also 4 rows deep on the core.  It has a particularly free flowing design, with no restrictors in the tanks. Now really hard to get hold of but I occasionally get one in from Spain. A re-core is 200 notes. I don't trust Ali/Plastic rads as there are too many very cheap copies on the market. I collect up original radiators and shrouds and then as required get the radiators refurbished. I don't 'modify' stuff any more. Grown past that point. I'm only interested in reliability. So as it came out of the box - electric or thermocouple - I don't care. Both are excellent if the vehicle is well maintained and not messed about with

When I worked for the BGS, I escorted a group of scientists (and the BBC) to the Danakil Depression. A well known warm place. We were in 105 'Cruisers (GS spec) and Land Rover Defender 130's (RoW spec). Standard radiators. Standard pretty much all the way through. Relatively lightly loaded and driven by experienced professional drivers. We were lucky as it was relatively cool and the Fire Winds weren't blowing, so it never went over 56degrees C (it can reach 60+ Degrees C). No overheating, no cooling issues (on the vehicles) - except the Air Con which failed miserably (wouldn't have used it anyway).

 

Just my pennyworth

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On 11/05/2017 at 2:58 PM, Bowie69 said:

Hmmm, I sort of see your point, but I still come back to the fact that your engine needed cooling, and the system used as little energy as possible (for an electric fan) to do the job, I'm at a loss as to why you see this as an issue, but there we are :)

You don't tend to hear viscous fans locking up while driving, but I bet they do :)

They shouldn't really, because you ought to have enough ram air that the rad is already doing its job and keeping the coolant temperature down.  But it is quite plausible that it'd lock up if you had high ambient temperatures, a blocked or restricted rad or some fault that either elevated the coolant temperature or a seized viscous hub.  Then again, any of those conditions, apart from the hub seizure, would activate electric fans too.  How many times have you seen mud caked vehicles by the side of the road on the way home from Billing and other shows, where they couldn't be bothered to hose the mud off the rad?

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41 minutes ago, honitonhobbit said:

"Heat Wave for Europe" - Maybe change that to Northern Europe and Scandinavia. Large parts of Russia, Southern Europe, The Balkans and The Peloponnese regularly get higher average temperatures.

Slightly O/T (Lord Forbid) but still on cooling. One of the mods we've fitted in the past, to vehicles going to Southern Europe, North Africa etc., if known to suffer from a less than adequate cooling system is the old VM 2.4/2.5 TD rad. I allows the fitting of a standard intercooler but is wider than a Tdi rad. It's also 4 rows deep on the core.  It has a particularly free flowing design, with no restrictors in the tanks. Now really hard to get hold of but I occasionally get one in from Spain. A re-core is 200 notes. I don't trust Ali/Plastic rads as there are too many very cheap copies on the market. I collect up original radiators and shrouds and then as required get the radiators refurbished. I don't 'modify' stuff any more. Grown past that point. I'm only interested in reliability. So as it came out of the box - electric or thermocouple - I don't care. Both are excellent if the vehicle is well maintained and not messed about with

When I worked for the BGS, I escorted a group of scientists (and the BBC) to the Danakil Depression. A well known warm place. We were in 105 'Cruisers (GS spec) and Land Rover Defender 130's (RoW spec). Standard radiators. Standard pretty much all the way through. Relatively lightly loaded and driven by experienced professional drivers. We were lucky as it was relatively cool and the Fire Winds weren't blowing, so it never went over 56degrees C (it can reach 60+ Degrees C). No overheating, no cooling issues (on the vehicles) - except the Air Con which failed miserably (wouldn't have used it anyway).

 

Just my pennyworth

However, I note that most of the people in this thread and on this forum aren't in the regions you mention, so I didn't really feel the need to include them as the debate is mostly centred on what everyone prefers for where they live. 

Your final paragraph is interesting, however nice new diesel Defenders are a long, long way from a '60s-tech V8 Range Rover. I don't think they came out of the factory ready for somewhere like where I live. 

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7 minutes ago, Davo said:

Your final paragraph is interesting, however nice new diesel Defenders are a long, long way from a '60s-tech V8 Range Rover. I don't think they came out of the factory ready for somewhere like where I live. 

Partly my point. Those defenders were in prime condition. Well serviced, relatively new, nurtured and no abused. I have a feeling that when the RRC was new it probably was up to the job - just. Read the factory off road driving manual and it often mentions what to do when a vehicle overheats - an expected scenario in the olden days when heavy towing or driving in sunnier climes. And that was pretty much any vehicle - including Toyota, Nissan, Jeep and maybe even, very occasionally G wagen

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Hoo boy, that's certainly true. Sadly, a new 130 has always been far beyond my resources! 

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:lol:

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