Alot of this is posted from my private build thread, so please forgive me if it switches from past to present tense and somewhere in between....

The need for a thermofan setup was born through necessity when I converted to a gilmer pulley setup:
http://ozdat.com/forum/viewtopic.php?f=28&t=24510



The standard fan doesn't fit on the new pulley, it's noisy, ugly and doesn't work all too well without a shroud. People say it also saps power, but I won't comment on that because I haven't tested it myself.

The first issue of installing a thermodan on your datsun is the lack of a thermoswitch. Most newer cars have them built in, so if you are using a radiator from a modern vehicle, first check for a thermoswitch or a provision for one. If you are getting an aluminium radiator, then you may be able to ask for an appropriate hole to be drilled and tapped to accommodate a switch.

But i like my old clunky 200b radiator, so I needed a different method of switching the fan on when I needed it.

I originally bought a davies craig controller but was less than impressed.
It's way too complex for what it needs to be, it will look messy and i don't want a **** dial!

Generally if i'm upset about something, i go to sleep and sometime during the night I'll get an idea and figure out an awesome way of fixing it. Sometimes it's complete BS but sometimes it's brilliant. I think my subconscious is a genius, I just wish I could use that part of my brain when i was awake!! Anyways, if i don't think of a way to fix it, it's usually not the right way of doing something and a good sign to scrap it.

I have ordered a TFS106 thermofan switch thru work.


I already have lying around an adaptor thing for a davies craig sender for an EWP controller. I'll be drilling out the existing 1/4" thread and tapping a new thread at M14x1.5 which will enable me to run this nice, simple switch.

Pics from trying out the switch last night:
pokes thru above the fins ok






it seems like a very crude way of controlling a thermofan and I'm not convinced at all. I reckon it would be near impossible to stop it leaking too.....

Now some people have asked me if the switch temperature was a little on the high side.
From what I can see on the interwebs, the car's supposed to run at about 90deg operating temp.
I also converted the Farenheit numbers on my factory gauge and it looks like the gauge agrees with that approximate temperature.

so when it goes over by 5deg the fan will turn on, then turn off again when it's back to optimal temp.
Also, the threads on the other ones are not suitable for my application which made the decision even easier

This is the adaptor thing i've got lying around that I'm going to re-tap to suit the switch.
Bought it for $5 a few years back at the same sort of sale i bought my roof racks from

http://www.daviescraig.com.au/Controlle ... tails.aspx

knew it would come in handy some day....

Supercheap sells an alloy one, or you can order these ones in for cheaper. The alloy ones are also harder to tap to the correct size

Ok, i'm waiting for a bunch of sh*t to arrive but i'm working with what i've got for now.
The thermofan is a calibre 12" unit from Supercheap.
Sizing it up... in this picture you can see the hose adaptor thing sitting there waiting for a good tapping and a switch to be installed.
The loom hanging out over the bumper is the alternator loom which has had wires added to it for the switch seeing as the switch will be in close proximity to the alternator - so no extra looms (your car is most likely different as mine is deloomed)

Loose cable won't do

Fixed

Mounted up... it's offset which enables room for an oil cooler if i install one down the track

It's strange, the fan came with everything you need to wire it up to the car via a thermoswitch EXCEPT the male end of the plug on the fan...... strange. Luckily I had one from a car i parted out - i kept all of the plugs and long wires from the loom and it's been extremely handy.
How it sat this morning before work:

more wires hanging out the front, it's the thermofan wiring, just need the switch in order to finish my install then it will all be hidden away.





time to fit the thermoswitch.

m14x1.5 thread requires a 12.5mm drill bit.
i don't have the tap handle so i used a 10mm spanner with much success

testing the thread

looking good, just need to clean up the hole a bit, then when it's tight it should sit about flush.

Thread tape 'just in case'

niiiice


Choppy choppy on my nice new hose

winner

I temporarily reassembled the alternator this morning and I've got room to twist the sensor down a bit so it's essentially invisible

Feels great to have the wiring done and grill back on!


end product:

Painted the fan motor cover - it stood out too much.


So, wiring goes like this:
'on' +ve -> fuse -> relay
'on' +ve -> fuse -> thermoswitch -> relay
relay -> thermofan +ve
earth -> relay
earth -> thermofan -ve

So +ve goes to the switch, when in the correct temperature range, it closes and lets the +ve through to the relay, the relay switches on and lets the +ve through to the fan which activates the fan. Earths are consistent.

Hope that helps!!

_________________

automotive clothing at www.burubado.com

Why did you locate the temp sender in the lower radiator hose? I would have thought the upper hose was a better place.

_________________
Rod

just thinking the same thing, the lower hose is the cool side while the upper the hot (which is where the temp sender should be) my 2c

is still a good set-up and i think i may borrow your idea with the adaptor, as mine weeps with the wire tucked in uder the hose at full pressure

_________________
Driving takes three abilities: Accelerating, braking, and turning.
More power only helps acceleration.
Lower weight helps all three.

Don't forget to turn the fan blade around - most come from the factory set up to 'pull'.

isnt it so your thermo fan isnt running constantly? obviously your temperature sender is mounted up there but the coolant temp you want to monitor is the temp coming out of the radiator?
and about running backwards if it from supercheap its as easy as switching wires around
ive been running an ICE adjustable tfs that was my first mistake but wondering how you find that temperature range? ive been looking for one for a z18 that will just screw straight into the thermostat housing but tridon dont seem to have the right thread to temp on off cross over.
anyway really nice write up

i wanted to measure the temp coming out, plus i didn't want to add a loom to my engine bay.
this way, if the car isn't moving and the radiator isn't cooling effectively, the temp coming out will be hot and will trigger the switch.

the calibre supercheap thermofan was set up as a push fan from factory.
best to check it though! get someone to hold it while you apply power to it, you will immediately know which way it's blowing.

if you need to switch it around, most fans have a small nut you undo to flip the blades over, then you just reverse polarity.

if you can't flip the blades over then you need a decent fan.

24TKman: i thought there would be issues with leaking....... i wasn't impressed........

_________________

automotive clothing at www.burubado.com

I think series III Bluebird had the thermofan switch in the bottom of the radiator, but it was a very low heat range, like 80-85 deg. So I reckon if you want to put the switch there, it has to be a cooler range than the usual 90-95.

L series optimum temp is 85 deg C. A 90 on 85 off would be the best switch IMO.

_________________
1928 Model A CC Pickup

If you want that temp you could use a TFS107 & use the low setting, not the high one. It has the same M14x1.5 thread too, so worst case scenario, if this switch doesn't work for me i can order one of those and screw it straight in.

I figure that the car's only going to get that hot when the car is stationary and I don't usually drive in traffic, so normally, the airflow through the radiator and the thermostat should keep everything in order. If i'm in a situation where the car is sitting in one spot, then the inlet and outlet temps will be about the same temperature due to a lack of airflow. If everything is working correctly, your thermofan shouldn't need to come on when you are moving, therefore the position should be irrelevant.

There is nothing stopping you sticking a sensor in the top hose though, it will just look a bit more messy.

_________________

automotive clothing at www.burubado.com

How did this all work out burubado ?

Did the temperature range of that sender work ok in the bottom hose ?

Keen to hear how well it all works as i'm about to do a similar set up in a 1600 rally car....