Outer Limits 4x4 Board

Just put an electric fan in my Rodeo but I want to wire it up so it cuts in at a predetermined temperature.
At the moment I have to watch the temp gauge and use it manually

I'm after a wiring diagram and details of the bits I need to hook it up in the radiator hose etc.

The fan was originally in a BMW and was controlled by the coolant temp sensor and ECU also with resistors so it could run at variable speeds.
I'm not really interested in setting it up like that I just want it to cut in and out when it needs to

Thanks, sudso

Go get a thermo switch, with a sensor that goes into your
top radiator hose, and you can set the temp so that it turns your thermo on and off.
I think there about $50 from repco or autobarn
As far as wiring goes get a relay, wire it to the batt if you want it to cool the car
after you've taken the keys out (remember this way the fan will run until it's cool, very annoying at 1am!!!)
Or wire it to the coil as your switch on the relay with the thermo switch in between.
relay
86 coil + switch or batt for constant power
85 earth
87 thermo
30 fuse batt
I hope this makes sense
if this is not correct someone pls correct me as this is how i'll be wirring mine up

sudso wrote:Just put an electric fan in my Rodeo but I want to wire it up so it cuts in at a predetermined temperature.
At the moment I have to watch the temp gauge and use it manually

I'm after a wiring diagram and details of the bits I need to hook it up in the radiator hose etc.

The fan was originally in a BMW and was controlled by the coolant temp sensor and ECU also with resistors so it could run at variable speeds.
I'm not really interested in setting it up like that I just want it to cut in and out when it needs to

Thanks, sudso

What model Beamer was it from? as most sedans run engine clutch fans. Make sure its not an a/c thermo or it'll be drawing air from the wrong direction.



Anyway. I was running thermo's in my GQ for a while and just had 'em wired up to a switch on dash.
In summer you needn't really bother with it as engine will warm up soon enough anyway
In winter if car runs too cold just switch it off untill temp reaches about half or so and switch on
I find it's more advantageous like this as you can switch it off when doing deep river crossings and bogholes. Therefore not forcing water against fan and throwing mud all over engine bay
And it's easier than wiring and plumbing up thermatic switches etc.

Pep wrote: As far as wiring goes get a relay, wire it to the batt if you want it to cool the car after you've taken the keys out (remember this way the fan will run until it's cool, very annoying at 1am!!!)

Why do people do this?

Having the fans on while the engine is not running does stuff all.
All this does is cool the radiator - NOT THE ENGINE.

You need the water pump to circulate the coolant to cool the engine.

GQ Bear wrote:

sudso wrote:Just put an electric fan in my Rodeo but I want to wire it up so it cuts in at a predetermined temperature.
At the moment I have to watch the temp gauge and use it manually

I'm after a wiring diagram and details of the bits I need to hook it up in the radiator hose etc.

The fan was originally in a BMW and was controlled by the coolant temp sensor and ECU also with resistors so it could run at variable speeds.
I'm not really interested in setting it up like that I just want it to cut in and out when it needs to

Thanks, sudso

What model Beamer was it from? as most sedans run engine clutch fans. Make sure its not an a/c thermo or it'll be drawing air from the wrong direction.



Anyway. I was running thermo's in my GQ for a while and just had 'em wired up to a switch on dash.
In summer you needn't really bother with it as engine will warm up soon enough anyway
In winter if car runs too cold just switch it off untill temp reaches about half or so and switch on
I find it's more advantageous like this as you can switch it off when doing deep river crossings and bogholes. Therefore not forcing water against fan and throwing mud all over engine bay
And it's easier than wiring and plumbing up thermatic switches etc.

Dont know what model Beema it came from. It was attached to the radiator in the Bundy I bought a while ago. Its a Seimens/VDO fan with the BMW insignia on it so it would be an OEM unit. It's directional only, front mount and works a treat. Gutsyest cooling fan I've ever known!
Got it wired up to the battery via a 70A relay and a 50A fuse as it blew the 30A fuse the first time I switched it on Must draw a heap of current when starting up and the idle drops about a hundred rpm too.
Just gotta remember to keep my eye on the temp gauge.

Ralf the RR wrote:

Pep wrote: As far as wiring goes get a relay, wire it to the batt if you want it to cool the car after you've taken the keys out (remember this way the fan will run until it's cool, very annoying at 1am!!!)

Why do people do this?

Having the fans on while the engine is not running does stuff all.
All this does is cool the radiator - NOT THE ENGINE.

You need the water pump to circulate the coolant to cool the engine.

Stops heat soak.
Circulation is a cooling effect for the engine aswell but minimally.