how does fan at front of radiator work???

[beefcream]

hey,

i have a question.. i have removed my clutch fan while fitting my gilmer drive and have removed charcol canister etc. i have chopped up my ford au twin thermos ready to bolt up but not sure wats the best method for a switch.

my main question is what does that fan behind the bumper do (the suposed aircon fan) cause i dont run aircon at all and i noticed on a test drive it turned on when the car temp got roughly half way. if this is the case i can hook up my au thermos to this and remove it along wif the aircon radiator panel in front on the main radiator.

[justbad4you]

MAIN QUESTION >? >>thermo fan

hey,

i have a question.. i have removed my clutch fan while fitting my gilmer drive and have removed charcol canister etc. i have chopped up my ford au twin thermos ready to bolt up but not sure wats the best method for a switch.

my main question is what does that fan behind the bumper do (the suposed aircon fan) cause i dont run aircon at all and i noticed on a test drive it turned on when the car temp got roughly half way. if this is the case i can hook up my au thermos to this and remove it along wif the aircon radiator panel in front on the main radiator.

some of the vr/vs came with an extra thermo fan

[soop]

I think its there to help the AC condenser. You sure it starts up with temperature?

[justbad4you]

hey,

i have a question.. i have removed my clutch fan while fitting my gilmer drive and have removed charcol canister etc. i have chopped up my ford au twin thermos ready to bolt up but not sure wats the best method for a switch.

my main question is what does that fan behind the bumper do (the suposed aircon fan) cause i dont run aircon at all and i noticed on a test drive it turned on when the car temp got roughly half way. if this is the case i can hook up my au thermos to this and remove it along wif the aircon radiator panel in front on the main radiator.

Thermo fan shouldn't come on unless the coolant temperature sensor has told the ECU to turn it on, and the condensor fan should only come on when the A/C is turned on, or the compressor clutch is engaged. The thermo fan might come on as well, to help keep the coolant temperature regulated with the extra load on the engine.

I think there is a fail safe with the coolant sensor, in that if it is buggered completely, it continually runs the thermo fan as a precaution to prevent overheating

[soop]

Yeah but with a 5ltr there is none of that. (for a v6 your correct).

With the 5ltrs I always bunged a tempsensor into the radiator tank and used an analogue adjuster to set the temp at which it it will throw an internal switch to power up the thermo fans.
About the only thing I ever used from the car was 12volt power source and an earth. Everything else needs to be done from scratch.

[BlackVXGTS]

Yeah but with a 5ltr there is none of that. (for a v6 your correct).

Not correct. Refer to the attached from the GMH VS workshop manual:

The V8 engine has a water pump driven radiator fan incorporating a semi-fluid hydraulic fan clutch. This engine-driven fan provides the primary means of moving air through the engine radiator.
On vehicles equipped with air conditioning, an additional electric motor driven fan is placed in front of the A/C condenser. The electric fan will be turned ON when the engine cooling fan relay is energised by the ECM/PCM.
Electric fan will be “ON,” controlled by the ECM IPCM, if any of the following is present:
- Engine coolant temperature exceeds 110 degrees C. (After ECM /PCM turns fan ON - it will run until coolant temperature is below 110 degrees C.)
- An engine coolant temperature sensor failure is detected (refer DTC 14 15, 16, or 17 Charts).
- A/C request signal is received and vehicle speed (VSS input) is less than 64 km/h.
- Field service mode is active. (Ignition ON, engine stopped and DLC diagnostic esr terminal earthed.
The engine cooling fan relay can also be enabled by the A/C pressure switch. The A/C pressure switch will provide a path to earth if the A/C pressure becomes too high above approximately 1770 kPa.

[beefcream]

Not correct. Refer to the attached from the GMH VS workshop manual:

The V8 engine has a water pump driven radiator fan incorporating a semi-fluid hydraulic fan clutch. This engine-driven fan provides the primary means of moving air through the engine radiator.
On vehicles equipped with air conditioning, an additional electric motor driven fan is placed in front of the A/C condenser. The electric fan will be turned ON when the engine cooling fan relay is energised by the ECM/PCM.
Electric fan will be “ON,” controlled by the ECM IPCM, if any of the following is present:
- Engine coolant temperature exceeds 110 degrees C. (After ECM /PCM turns fan ON - it will run until coolant temperature is below 110 degrees C.)
- An engine coolant temperature sensor failure is detected (refer DTC 14 15, 16, or 17 Charts).
- A/C request signal is received and vehicle speed (VSS input) is less than 64 km/h.
- Field service mode is active. (Ignition ON, engine stopped and DLC diagnostic esr terminal earthed.
The engine cooling fan relay can also be enabled by the A/C pressure switch. The A/C pressure switch will provide a path to earth if the A/C pressure becomes too high above approximately 1770 kPa.

Legend! this is the info i was lookin for
so my suspision was correct and i can use that as a my connection for thermo fans

[wamboin23]

you could, but shouldn't.

AU twin thermos draw way to much current at startup for standard setup.

Use the connection to trigger a relay, or pref. two relays, and two inline fuses directly from battery. around 25amps each. Heater fan runs from same fuse link, so if you've got the heater fan going full bore, and the thermos come on, very good chance the fuse will blow.

Also, 110°C is a bit high for the thermo fans to be coming on.

[justbad4you]

howdy soop...... i thought he was talinkg about a v6?> not worry all is good.cheeers

Yeah but with a 5ltr there is none of that. (for a v6 your correct).

With the 5ltrs I always bunged a tempsensor into the radiator tank and used an analogue adjuster to set the temp at which it it will throw an internal switch to power up the thermo fans.
About the only thing I ever used from the car was 12volt power source and an earth. Everything else needs to be done from scratch.

[soop]

Not correct. Refer to the attached from the GMH VS workshop manual:

The V8 engine has a water pump driven radiator fan incorporating a semi-fluid hydraulic fan clutch. This engine-driven fan provides the primary means of moving air through the engine radiator.
On vehicles equipped with air conditioning, an additional electric motor driven fan is placed in front of the A/C condenser. The electric fan will be turned ON when the engine cooling fan relay is energised by the ECM/PCM.
Electric fan will be “ON,” controlled by the ECM IPCM, if any of the following is present:
- Engine coolant temperature exceeds 110 degrees C. (After ECM /PCM turns fan ON - it will run until coolant temperature is below 110 degrees C.)
- An engine coolant temperature sensor failure is detected (refer DTC 14 15, 16, or 17 Charts).
- A/C request signal is received and vehicle speed (VSS input) is less than 64 km/h.
- Field service mode is active. (Ignition ON, engine stopped and DLC diagnostic esr terminal earthed.
The engine cooling fan relay can also be enabled by the A/C pressure switch. The A/C pressure switch will provide a path to earth if the A/C pressure becomes too high above approximately 1770 kPa.

Admitedly never touched a VS 5ltr. VR is the most recent in a commodore.

[justbad4you]

did you do it yet? post some pic if poss

hey,

i have a question.. i have removed my clutch fan while fitting my gilmer drive and have removed charcol canister etc. i have chopped up my ford au twin thermos ready to bolt up but not sure wats the best method for a switch.

my main question is what does that fan behind the bumper do (the suposed aircon fan) cause i dont run aircon at all and i noticed on a test drive it turned on when the car temp got roughly half way. if this is the case i can hook up my au thermos to this and remove it along wif the aircon radiator panel in front on the main radiator.