Hello.

Mine is a facelift V12 '92(with black bumper)
I am planning the electric fan conversion using the existing fan shroud and 17" 2 speed Ford fan (for Thunderbird/Taurus)
I am controlling it with a 3 pin thermo switch which I can screw on instead of the switch on the water pump.
Ref the sub fan, I bought an aftermarket 1700cfm 12" fan yet to fit.


I have to decide which fan switch to use, but I a wondering which to buy.
I would appreciate it when you give me any advice.
Here are the candidates;

1. Closing Temperature [°C]: unknown (low speed off)
Shut-off Point [°C]: unknown (high speed off)
Opening Temperature [°C]: 85 (low speed on)
Switch Point [°C]: 100 (high speed on)
* this is a diversion of X300 fan switch

2. Closing Temperature [°C]: 79
Shut-off Point [°C]: 85
Opening Temperature [°C]: 87
Switch Point [°C]: 93

3.
Closing Temperature [°C]: 88
Shut-off Point [°C]: 92
Opening Temperature [°C]: 93
Switch Point [°C]: 97


What matters will be what temp is the best for a V12 engine... But I have no idea.
I don't think 3 is good, for the closing temp is too high... The other spec doesn't seem so bad though.

1 and 2 has almost the same starting temp, but the temp for switching to high speed is different. Is 100 deg/C too high? Or maybe 93 deg/C too low?

Any advice will be appreciated.

 

I just wired them both to the water pump switch with a live feed going to the wire off of n04 on the blue diode pack which makes them stay on till the engine cools, I cant see the point in making things over complicated, when the original switch is quite adequate

 

maybe i just need my coffee but i am very confused by the data on your switches.

By opening and closing do you mean the switch itself?? Why would the switch be opening at a higher temperature than a lower one?

As a poor college student with a busted temperature switch I just straight wired my electric fan to come on with the ignition when I replaced it.

Sure it reduces the life of my cheapo fan, but it has no ill effects on the cooling system itself, so I don't really care for now.

 

I just copied & pasted the data, but I think opening means "on" and closing means "off", so it is not about the switch itself. I also confused at first though.

I want to control the fan neatly because I want to save electricity and fuel. When you turn the fan on while cold, the fuel will stay rich and waste gas. No to mention electricity.

Okay, then could someone tell me how high the temp is when the coolant temp gauge is in the middle? I will consult that temp to decide the sensor.

 

I strongly suspect Jaguar intended for 'middle of the N' to be about 82ºC- 88ºC .....thermostat rating range. That's what most manufacturers do, it seems.

The old barrel gauges are not very accurate, though, so don't be fooled.

You certainly don't want the fans coming on sooner or longer than required....that's the whole idea of e-fans.

Maybe have low speed kick in at 93ºC and high speed at 98ºC or so?

More later, gotta get some work done !

Cheers
DD

 

Thank you for the info all the time Doug.

Yes, that is what I am talking about! Sorry for my poor English...
I will keep on looking for some more switches which will be likely to be used.

 

If your fan shroud is the same size as on the pre-facelifts, a 17" bladed fan will not fit into the shroud. Same with a 12" in the auxiliary fan shroud. 16" and 11" blade diameters are the maximum sizes the shroud will take.

Good luck with the chnage. Well worth doing;

Greg

 

Hi Greg, thank you for the input. I must have made a mistake, the sub fan will be definitely too large... I can sell it off or maybe I can cut off the shroud.
I think the main fan must be okay, for the shroud is almost 18" and the fan I bought is 17.3". I can't say anything until I actually see the fan I bought... But the fan blade itself is 17" in the later model (at least on mine) so that'll fit.

 

In my case I had bought a 17" and a 12" fan before I realised the problem. So I removed the shrouds completely, they just unbolt. They are not needed because electric fans come with their own shroud anyway. Even with no shroud, it is a big squeeze to fit an 12 and a 17 across the rad at all.

But the main problem is how to mount them. You can fix them to the radiator fins, but I do not like this as I worry about the rad fracturing from the fan vibration. I made up a little fan chassis from aluminium square tube to hold the two fans and fixed the chassis to the toprail and the bottom cross member in rubber mountings. You could use the same mountings as the old shroud used if they are OK.

Good luck
Greg

 

Thank you Greg, when I receive the fan I will report what it is like. I hope the large fan fit...

 

Well maybe the person who listed it is confused but "open" means disconnected and "closed" means the circuit in completed.


Either way the car will NOT run rich if the fans are constantly running.
If the car is not yet up to temperature the thermostats are not open, the fans are helping cool the radiator and the coolant that is inside it, but that coolant is not being circulated through the engine.

Having electric fans always on will technically give the alternator more work to do, but you are never going to see that at the pumps

 

Hi sidescrollin, thank you for the correction. You're right, I was mixed up with the knowledge of fan control and radiator temp.
I found out that the fan I am going to use pulls serious amount of electricity when hot, and now I understand the fan switch sits where the coolant that is cooled down through the radiator comes, I will go for the X300 temp switch. As you said it will make no problem when it starts to rotate while the coolant is not so high.

Thank you all for the information.

 

This device:

AutoSpeed - $25 Temperature Controller and Display!

can control a relay based on temperature readings and has a digital temperature display

having a hysteresis feature, they can be set for example to turn on a relay at 195*F, but not turn off again until the temperature has dropped to 190*F to avoid constant cycling

there is also a programmable offset so that the sensor can be adapted to temperature offset due to heat loss through a cooling jacket.

ebay has them in both centigrade and fahrenheit versions .. as well as 12vdc and mains operated displays ... make sure you get the right one, they all look the same

$20 to $25

 

Hi plums, many thanks for the info, this is fantastic! I will buy and try this one. I have to buy a controller for the auxiliary fan anyway. No controller with a digital display can be bought at this price... Thank you again