Not engaged does not mean it stops. Of course it turns, but it is not being driven as such, there is a difference. You can stop a Viscous fan with your hand that is not engaged, bit more difficult when it is engaged.
The way I see it is as follows. The viscous is unreliable there are regular reports of overheats that turn out to be a duff viscous. A good viscous cannot be stopped with a rolled up newspaper when the engine is hot, therefore it is being driven even if not needed. It's noisy.
On the plus side, the electric fans rarely run, With the cowl removed RAM air provides all the cooling needed even at low speed in hot weather. Access to the front of the engine for belts etc is greatly improved.
For example when the plastic water pump failed it was a 15 minute job to fit a replacement.
I don't much care what other people who have not tried this think, I have proved the electric fans over a long period of time in many conditions towing up to 3 tonnes with not a hint of an overheat.
 
The way I see it is as follows. The viscous is unreliable there are regular reports of overheats that turn out to be a duff viscous. A good viscous cannot be stopped with a rolled up newspaper when the engine is hot, therefore it is being driven even if not needed. It's noisy.
On the plus side, the electric fans rarely run, With the cowl removed RAM air provides all the cooling needed even at low speed in hot weather. Access to the front of the engine for belts etc is greatly improved.
For example when the plastic water pump failed it was a 15 minute job to fit a replacement.
I don't much care what other people who have not tried this think, I have proved the electric fans over a long period of time in many conditions towing up to 3 tonnes with not a hint of an overheat.

Viscous fan is a very reliable unit. They are not just on or off as you seem to think. They are variable subject to temp if working properly. The only time there should be any roar from a viscous is for a few seconds after a cold start until centrifugal force returns the medium back to storage. Crap maintenance and not knowing what to look for when carrying out a service cause the failures. The medium is constantly circulated subject to temp and valve opening. If you start up and allow the engine to reach normal temp at idle and you cannot stop the viscous with a hand there is something wrong with it. Have done this hundreds of times so don't say it is not possible. If you don't know what you are doing DON'T try it.
 
Viscous fan is a very reliable unit. They are not just on or off as you seem to think. They are variable subject to temp if working properly. The only time there should be any roar from a viscous is for a few seconds after a cold start until centrifugal force returns the medium back to storage. Crap maintenance and not knowing what to look for when carrying out a service cause the failures. The medium is constantly circulated subject to temp and valve opening. If you start up and allow the engine to reach normal temp at idle and you cannot stop the viscous with a hand there is something wrong with it. Have done this hundreds of times so don't say it is not possible. If you don't know what you are doing DON'T try it.
I didn't say the viscous was ON or OFF, I said it is not possible to stop with a rolled up newspaper when the engine is hot, the standard test for a duff viscous, that proves there is still drive to the fan via the fluid coupling. You may well want to try stopping the fan with your hand, get one that has locked and you are likely to suffer damage. The coupling is a variable vane device as far as I know, I have one I can cut open to check. What do you do for maintenance on the viscous? They are supposed to be maintenance free.
There should never be a solid drive, if there was the fan would over speed resulting damage. The degree of drive is as you say, temperature dependant, the point is that there is always a degree of drive.
There are loads of reports of the viscous fan failing on LZ. On non LR vehicles viscous fans seem to be reliable, shame the same cannot be said of the LR viscous, I've got 3 duff ones, one from each of my P38's. My scrapper suffered a cracked head before I acquired it, due to repeated overheating the probable cause of which was the duff viscous, not discovered until too late.
 
Viscous fan is a very reliable unit. They are not just on or off as you seem to think. They are variable subject to temp if working properly. The only time there should be any roar from a viscous is for a few seconds after a cold start until centrifugal force returns the medium back to storage. Crap maintenance and not knowing what to look for when carrying out a service cause the failures. The medium is constantly circulated subject to temp and valve opening. If you start up and allow the engine to reach normal temp at idle and you cannot stop the viscous with a hand there is something wrong with it. Have done this hundreds of times so don't say it is not possible. If you don't know what you are doing DON'T try it.

I didn't say the viscous was ON or OFF, I said it is not possible to stop with a rolled up newspaper when the engine is hot, the standard test for a duff viscous, that proves there is still drive to the fan via the fluid coupling. You may well want to try stopping the fan with your hand, get one that has locked and you are likely to suffer damage. The coupling is a variable vane device as far as I know, I have one I can cut open to check. What do you do for maintenance on the viscous? They are supposed to be maintenance free.
There should never be a solid drive, if there was the fan would over speed resulting damage. The degree of drive is as you say, temperature dependant, the point is that there is always a degree of drive.
There are loads of reports of the viscous fan failing on LZ. On non LR vehicles viscous fans seem to be reliable, shame the same cannot be said of the LR viscous, I've got 3 duff ones, one from each of my P38's. My scrapper suffered a cracked head before I acquired it, due to repeated overheating the probable cause of which was the duff viscous, not discovered until too late.

Anyway.... Went to the hospital and all was good.
Now it has settled overnight, one patch of a couple of lost layers and dark redness around the elbow and a smashing yellow bubble of water..
As much as I want to fit an all alloy rad, I think the nissens rad will go back in so I can install the electric fan and shroud again. I reckon looking back over the amount of times the rad has been changed in the 18yrs, they have been poor quality.
So.... nissens it is.:)
 
Saw that, thank you.
The only problem is it's thicker than the original or replacement and means the electric fan will come up against the engine. It's already mm of the belt adjuster as it is.
Direnza do one as well. Saw some bad reviews on the tube of U.....
 
I didn't say the viscous was ON or OFF, I said it is not possible to stop with a rolled up newspaper when the engine is hot, the standard test for a duff viscous, that proves there is still drive to the fan via the fluid coupling. You may well want to try stopping the fan with your hand, get one that has locked and you are likely to suffer damage. The coupling is a variable vane device as far as I know, I have one I can cut open to check. What do you do for maintenance on the viscous? They are supposed to be maintenance free.
There should never be a solid drive, if there was the fan would over speed resulting damage. The degree of drive is as you say, temperature dependant, the point is that there is always a degree of drive.
There are loads of reports of the viscous fan failing on LZ. On non LR vehicles viscous fans seem to be reliable, shame the same cannot be said of the LR viscous, I've got 3 duff ones, one from each of my P38's. My scrapper suffered a cracked head before I acquired it, due to repeated overheating the probable cause of which was the duff viscous, not discovered until too late.

I refer you to post #62.
 
Right then, strip down time.
New rad came, nissens unit. Thinner core than the one it's replacing...
Split intercooler and duff belts.. all split.. so I'm going to go with datateks Aircon fan mod. I'm going to lose the shroud I made and link all the fans together so when I go offroading in the hotter weather I can rely on more air being moved over the radiator.
A little demoralised at the moment but my arm is much better.:D
 
IMG_20190215_114851.jpg

Now it's dried out, not as big as first thought.
IMG_20190215_114843_1.jpg

IMG_20190215_114837.jpg
IMG_20190215_114832.jpg
more pics tomorrow. ;)
 
I put a Britpart rad in my V8 :confused:, the old one ****ed water out the bottom as fast as it was poured in. :D

Viscous fan seems up to the job IMO pulling a few large heavy trailers around a field in mid summer in 30+ degree heat and not a sign of an overheat. o_O

Mind you i've got a spare hanging on the wall, just in case. :)


Nice grill Mark..

Homemade?
 
I put a Britpart rad in my V8 :confused:, the old one ****ed water out the bottom as fast as it was poured in. :D

Viscous fan seems up to the job IMO pulling a few large heavy trailers around a field in mid summer in 30+ degree heat and not a sign of an overheat. o_O

Mind you i've got a spare hanging on the wall, just in case. :)


Nice grill Mark..

Homemade?
The grill isn't on there in these pictures Henry.
3104d6e8ad999c4a622a99b036c5a1ca.jpg
Thats it all covered up. It needs a bit more black Matt as the fixings I used had started to rust and infected the grill....along with the stone chips... With vinegar mmmmm.
 
I will not lean over my rad again after seeing that split, wouldn't have thought they would do that :eek:

Like that grill looks OE and makes a P38 look Classic-ish. The fact I find it quite sexy means I am probably reading too many of @Henry_b 's threads:p

Anyway, glad to hear you are okay after your ordeal and back to your P38-potching self ;)
 
I will not lean over my rad again after seeing that split, wouldn't have thought they would do that :eek:

Like that grill looks OE and makes a P38 look Classic-ish. The fact I find it quite sexy means I am probably reading too many of @Henry_b 's threads:p

Anyway, glad to hear you are okay after your ordeal and back to your P38-potching self ;)
Why thank you very much;).
 

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