Everything can break.
The most important thing is airflow, either the fan does the job, or not. The pro of electric is it only draws power and operates when it's required. Viscous fans don't draw electric power, but do sap power directly. They generally have a very high flow rate
The most important thing is airflow, either the fan does the job, or not. The pro of electric is it only draws power and operates when it's required. Viscous fans don't draw electric power, but do sap power directly. They generally have a very high flow rate
Retroanaconda
Well-Known Member
Common misconception that viscous vans draw power all the time. The whole point of the viscous coupling is that it only engages when the engine warms up. When not engaged the fan will ‘idle’ and spin with the engine but you’ll be able to stop it easily and it will put no load on the engine. You’d also need a hell of an electric fan to match the power of the viscous when it is fully engaged.
It’s one of those things that Land Rover got right - the only reason to change to electric would be if you physically couldn’t fit a viscous fan on, for example if fitting a different engine setup.
It’s one of those things that Land Rover got right - the only reason to change to electric would be if you physically couldn’t fit a viscous fan on, for example if fitting a different engine setup.
Tend to think this is right. I changed from viscous to electric and was firstly shocked by how little I needed to switch it on and secondly that it made no difference at all to mpg.
Also I think it is true to say that if a viscous fails, it fails in "locked on" mode which won't make the engine overheat. Not sure you could say the same about an electric one.
Once you get a car running a bit above 30 mph the fan does little compared to the air thrust throught the rad by its forward motion. Either fan!
RangeRoller dt
Well-Sprung Member
Think of it like a kettle - you get a better cuppa off the stove.
Viscous works incrementally whereas lectric switches on/off at certain temperatures only, like leaving it boil then cooling it then letting it boil again
Apologises for the terrible analogy in advance
Viscous works incrementally whereas lectric switches on/off at certain temperatures only, like leaving it boil then cooling it then letting it boil again
Apologises for the terrible analogy in advance
Think that's a great analogy! Like making coffee on the stove in an old fashioned percolator rather than boiling a kettle!
And for the record, I have left the viscous on my D2 and would change the D1 back if I could be bothered and was driving it now!
Landy Hugger
Member
Great thread.
Just the two question I was think about.
How do you check a viscous fan that it’s working properly?
Also can up upgrade a viscous fan
Just the two question I was think about.
How do you check a viscous fan that it’s working properly?
Also can up upgrade a viscous fan
discool
Well-Known Member
The fan isn’t viscous it’s the coupling that is, so in theory if a larger fan could be fitted or a fan with a few more blades its an upgrade, like the the difference in the number in blades between the Tdi and V8 which requires extra cooling. And there’s couplings with different temperatures settings so matched to a specific LR engine.
If the coupling is working ok the fan will roar a bit like a turbine for fifteen seconds give or take when starting with a cold engine, the turbine sound could return on the heat of the engine, for example stuck in traffic on a hot summers day as it does on my disco.
discool
Well-Known Member
So how u do that, break into it, drain the fluid and then weld together the chambers. simpler the keep the viscous then install an electric fan manually or automatic or both to switch on if you think it’s need.
landy-lee
Well-Known Member
Nope just weld the nut that screws on to the pulley to the viscous housing.
discool
Well-Known Member
Ok that would work if a weld would take ? i don’t do welding, but the nut is steel and the coupling is alloy on a D1 & 2
If for 1 minute I thought you were going to drive your landy to Morocco, I think you would need to worry about more than a fan.
But!!!
For me there are a few ideas/ways.
1. Bigger rad.
2. A supplemental fan outside to “push air”
3. Get more blades on viscous (mentioned earlier)
4. Fly there and hire somebody else landy and don’t worry about it
J
landy-lee
Well-Known Member
If for 1 minute I thought you were going to drive your landy to Morocco, I think you would need to worry about more than a fan.
But!!!
For me there are a few ideas/ways.
1. Bigger rad.
2. A supplemental fan outside to “push air”
3. Get more blades on viscous (mentioned earlier)
4. Fly there and hire somebody else landy and don’t worry about it
J
yes i am driving to morocco.
i hear engines get a bit hot when thrashing up the sand dunes so im just chucking some ideas around.
landy-lee
Well-Known Member
yes can use brazing rods or a 2 part adhesive/cement.
well hats off to you Lee
Then I wouldn’t mess with the viscous fan.
Perhaps consider 1&2 of my suggestions.
what else you taking? and I am look forward to seeing a Fred on the journey
J
landy-lee
Well-Known Member
Cheers mate i will.well hats off to you Lee
Then I wouldn’t mess with the viscous fan.
Perhaps consider 1&2 of my suggestions.
what else you taking? and I am look forward to seeing a Fred on the journey
J
On the alisport web site they do say use a viscous fan for the best cooling and their rads cooling is 25% better.
I just wanted to know what people have done in the past.
RangeRoller dt
Well-Sprung Member
I fitted a permanently locked viscous. It Over cooled so it worked and got me through summer . A 300TDI viscous helps on p38D also as it’s bigger.
+1 fit both
Viscous for normal running then an electric you can turn on when its needed for extra airflow
+1 fit both
Viscous for normal running then an electric you can turn on when its needed for extra airflow
check a viscous by sticking a rolled up newspaper or magazine in it while it’s hot and running. If the paper stops it easily it’s had it.
Retroanaconda
Well-Known Member
It’s not necessary, the viscous will lock up under those conditions and give you exactly what you need when you need it. It will also not sap power off the engine the rest of the time, which is a problem that welding it up would give you.
Personally I don’t see any benefit in fitting an electric fan as well, unless you’ve got A/C condensers in front of the rad. The vehicle was designed to operate in desert and arctic environments, and everything in between.
To test a viscous you need the engine hot enough at low speed to engage it. Very difficult to achieve in UK ambient temperature other than by carrying a heavy load up a hill steep enough to need a low gear. You can use a heat gun to warm the coupling with the engine running though, which should get it to lock up.
