Thread: Thermo fan conversion on a d2 td5

export commodores use a heavier duty fan and these are options an Australian sold cars.
If you don't use the a/c you should not hear the low speed running.


also different method of operation. some commodore run the smaller fan at all times after the coolant has warmed up to circulate air under the bonnet.


VN-VR had a speed imput to turn off the fan when the car is moving.until it achieved higher temp.i would expect later cars to be the same.


I operated my disco 3.5 without a visco hub during winter months doing an easy comute.,the a/c fans only operate at traffic lights.

My understanding from reading of similar posts in the past is electric fans on TD5's don't' work.
It would appear that on the V8's they work well, more so with a good shroud.
IIRC once the TD5 radiator gets hot the electric fans(of any type) can't get the temperature down.

I would not remove the clutch fan, but add twin thermo fans like I have done to the front of the radiator inter-cooler set up to push air through. I have one set to come in around 90 deg c and the other comes on when the air conditioner is turned on. Makes a lot of difference in heavy stop start traffic and also helps with better flow to the larger inter-cooler. The ones I used were Davies Craig fans with the temp kit bought from Supercheap when they had them on sale, so basically got 2 for the price of one. It did take some slight modifications on the Defender support braces, had to cut and move, but then also used these supports as attachment points for the fans. Was a tight fit and took a little thought but not that hard to do. Personally I think LR should have done this as standard for Australian vehicles.
With the Defender with the bigger intercooler the Falcon and Commodore twin fans were too big to fit and would not have been able to fit the grill back on. A D2 may have more room.
I had a D2 V8 (wreck) before I left Esperance and I am fairly sure the V8 did have a thermo electric fan as standard as well as the clutch fan, may be wrong though. I know the Defender did not, but may have been an option as it is in the workshop manual for some models and does appear to have some wiring for this.
Cheers
Craig

Originally Posted by alien

My understanding from reading of similar posts in the past is electric fans on TD5's don't' work.
It would appear that on the V8's they work well, more so with a good shroud.
IIRC once the TD5 radiator gets hot the electric fans(of any type) can't get the temperature down.

Where do you get that information from? Any additional air flow will assist, more so at low speed heavy work. At high speed highway work they are no that much assistance.
Mine have made quite a bit of difference to the air con, keeping engine temps cool when the engine is working hard and a minor performance/economy gain.

Originally Posted by joel0407

I did the conversion to a 2f, FJ40. It really made a big difference to the power but on the down side, it got hot all the time. The Electric fans just cant pull the same amount of air as the engine driven.

Happy Days

The advice I have had is if you are going to do away with the engine driven clutch fan then you need electric fans on the inside of the radiator to pull air through the radiator and should still also have at least one on the front of the radiator to push air through as well. On most 4x4 just replacing the engine clutch fan with a single electric or even twin electric on one side will not suffice. The real advice I got and did was to leave the clutch fan in place and put twins on the front of the radiator, with one for air con and the other to assist with temps. Having said that I was also told that the clutch fan could be replaced, but unless you are talking performance vehicles such as race cars then really not worth it and should also be used in conjunction with an electric water pump. The standard Davies Craig fans can be set up to either push or pull air flow through the radiator. I have also seen on 300 tdi fans set up for the radiator and intercooler.

I am reluctant to enter into this one , although I have experimented a great deal over the years to keep Rovers cool.
The first question that comes to mind is why?
I know that greater fuel economy is often given as a reason and I think this is true in cool/cold climates like UK.

Then people say that electric fans cool just as well as Viscous often saying at the same time that viscous fans drag up to 7 BHP.
Now 7 BHP I once worked out to be equivalent to about 200amps .

Seeing electric fans are seldom more than say 22 amps for the pair, I find it hard to see how they can pass as much air.Also if you put much higher amp fans in bear in mind that even a 150 amp alternator does not produce much more than 20-30 amps at idle.

I remember putting a Mercedes 280 SE fan in My RRC in Saudi trying to keep it cool in up to 50 C. The 280SE in 1985 had about an 18 inch fan drawing lots of amps. It did help the viscous a lot. I had to hack the car about a lot to fit it.
My next adventure was a Porsche 924 turbo with a local aircon that would not stay cool. Turns out the PO had fitted 2 Davies Craigs pulling with no shroud.
I managed to buy an OE twin fan shroud from Porsche Germany and fitted 2 x VW Golf Bosch fans through a dual relay setup where one worked all the time and one when the aircon was on. The Porsche then stayed cool and actually cooled down when the aircon was switched on.

I guess that is a long winded way of saying that a comprehensive fan shroud is essential.

Another thing I hadn't thought of until I was in Saudi, is that as you drive along at 80Kmh the viscous fan is actually driven by the airflow and so is not a great drag on the engine. This was shown to me by my electric fans, as the bushes dried out and it took me a while to work out where the squeak was coming from, as the blades were being driven a quite a speed by the airflow..
All in all I am against having electric fans, as if Toyota and Land Rover STILL use VCs in their heavy duty 4Wds , then who am I to argue.
I think electric fans will be fine until you actually really need them, say climbing a sandhill on a 40c day. If you don't do that sort of thing then no problem.
Regards Philip A

Originally Posted by PhilipA

I guess that is a long winded way of saying that a comprehensive fan shroud is essential.

All in all I am against having electric fans, as if Toyota and Land Rover STILL use VCs in their heavy duty 4Wds , then who am I to argue.
I think electric fans will be fine until you actually really need them, say climbing a sandhill on a 40c day. If you don't do that sort of thing then no problem.
Regards Philip A

Hi Philip,

I am with you on the shroud, luckily apparently the Falcon EL fans are an almost perfect fit for a P38 radiator, not sure about the discos though

Edit; This post talks about the EL fans in a Disco http://www.aulro.com/afvb/2026410-post14.html

Also the latest Range Rovers use electric fans it seems

Regards
Steve

The other option is the FlexLite fans mentioned here

http://www.aulro.com/afvb/2024628-post12.html

Steve