Can this be wired to say on permanently and or when the viscous fan cuts in to aid cooling? It seems like a good idea to me?

It will cut in when needed anyway :)

Can this be wired to say on permanently and or when the viscous fan cuts in to aid cooling? It seems like a good idea to me?

You deffo don't want both on all the time bud.

The viscous fan should be running all the time that the engine is, the Aux fan should only come on when it detects overheating, around 95-98deg i think, or when it detects a fault in the ECU or the water temp sender sensor, if the fan (aux)comes on soon as you turn the key, the engine has one of these faults above.

If you want to chase a few more ponies, you could ditch the viscous fan altogether and fit an electric fan to the Rad engine side and have this cut in at 85deg, this will enable cold engine warm up quicker too.

smithy

The ONLY thing that will reduce the temperature of the engine when warm is the thermostat - doesn't matter what you do to the rad/cooling fans etc

if you want panic protection wire the fan into a switch

The ONLY thing that will reduce the temperature of the engine when warm is the thermostat - doesn't matter what you do to the rad/cooling fans etc

erm and whats that in relation to the above ?

smithy

So is the aux fan actually needed if all it's there is for a fail safe?, I thought I coul have it on all the time to aid cooling?

So is the aux fan actually needed if all it's there is for a fail safe?, I thought I coul have it on all the time to aid cooling?

it also takes the heat away from air con rad

erm and whats that in relation to the above ?

smithy

 

Can this be wired to say on permanently and or when the viscous fan cuts in to aid cooling?

 

It WON'T aid cooling!

 

If you want to chase a few more ponies, you could ditch the viscous fan altogether and fit an electric fan to the Rad engine side and have this cut in at 85deg, this will enable cold engine warm up quicker too

 

Not if the thermostat aint open! The only time to upgrade the fan cooling method is when the temperatures soar beyond the 'stat opening temperature where the rad is losing its eficiency....

Hi Andy, please explain why it won't aid cooling? i'm confused on that, surely if it's on it will?

Ok, the flow of coolant to the radiator from the engine is controlled by the thermostat. It will only allow enough water to pass to the radiator in order to keep the engine at 87deg C. IF the thermostat is fully open and the water pump is working its nuts off, then the cooling of the radiator is the problem. This never really happens though, the 'stat passes enough coolant to the radiator for cooling as is needed.....

Lee a simple test for yer when your zed is fully up and running.

Assuming you have an aftermarket temp gauge and decent thermostat on Day 1 see how long the car takes to reach 80 degrees from cold, on day 2 and in similar conditions remove the viscous fan and see how long the car takes to reach 80 degrees, the time should be shorter as the viscous fan is no longer spinning and keeping the rad water cool, reaching correct operating temp quicker wil enable boosting the engine quicker and the engine running effectively at the correct temp.

Whilst the thermostat is controlled by water temps, keeping it at the right temp in the rad means all coolant flowing through the entire system is operating the thermostat correctly. In the removing the entire viscous system, the engine is driving one less belt, hence a wee bit more power, if fitting an aftermarket electric fan with an 85 degree on/off switch, should the car reach this temp, the fan is so powerful it will reduce the rad water temp so quickly, cooler coolant is pumped around the system.

Leaving the existing AUX fan as is, will do more good than harm.

smithy

When the 'stat is closed, NO coolant flows!!!!

Thanks for that guys, makes a lot more sense now:), think i'll be leaving the aux fan as is!! afterall if the thermostat is closed restricting coolant to the rad then the aux fan will be cooling what is effectively "cool water", this then may keep the thermostat closed for longer and actually restrict water circulation, so potentailly harmful to the engine!! hmmm sometimes I think it's best to leave things as Nissan designed lol

So having just stripped out everything aircon related would I get any benefit from replacing the aux fan,ie is it used when the engine is hot or is it used for aircon only?

So having just stripped out everything aircon related would I get any benefit from replacing the aux fan,ie is it used when the engine is hot or is it used for aircon only?

I have a gut feeling that the aux fan is there predominantly for the aircon but also as a fail safe...

Its there for extra cooling also so leave it there :)

I have a gut feeling that the aux fan is there predominantly for the aircon but also as a fail safe...

 

the Aux fan should only come on when it detects overheating, around 95-98deg i think, or when it detects a fault in the ECU or the water temp sender sensor, if the fan (aux)comes on soon as you turn the key, the engine has one of these faults above.

smithy

 

smithy

Thx Smithy:), you and Andy have given me some good honest advice which I do appreciate!!