Defender gets hot, when working!

Viscous Fan Hub Replacement.

I had been using the Defender and on occasions the temperature needle would get near to the ¾ mark on the gauge causing me to panic. I had been flushing the radiator through, every time I changed the coolant, and also had changed the thermostat. This did not cure the problem, until I red a thread of  a Land Rover forum stating the symptoms could be the Viscous Fan Hub not working.

The Viscous Fan Hub is a clutch style mechanism with fluid contained within. When the fluid gets hot, the viscosity of the fluid changes and it moved to another part, causing the clutches to engage and turn the fan blades when the engine is hot.

A test is when you have run the engine for about 20 mins, or when the temperature gauge is ½ way, turn the engine off and open the bonnet. Make sure it’s not running. Try and turn the fan blades, if they are hard to turn, then the hub is working, however on mine it was just spinning with no effort needed. Obviously this unit had failed.

I tried buying the fluid, which is silicone oil from Toyota and drilling a hole in the front, and filling it up with the fluid, then plug the hole. This made it stiffer, however it was not working properly, so a new unit was required.

I purchased one from the UK at $80-00 Aus delivered. $100-00 cheaper than here in Aus.

Here are the steps to change the Viscous hub on a 200 Tdi Land Rover Defender.

The New hub

First of all ensure the item is the correct part. In this case part no. ETC7238

Then you need to get the tools ready.

1.    a Fan Hub spanner 32mm

2.     a 10mm Socket and Ratchet

3.     A bar round enough to fit in the hole on the fan pulley to lockit.

Once you have the tools it will take about 10 minutes tops to do, it only took me 5 mins, and its easy to do.

Place the 32mm spanner on the fan hub nut, and place the small bar into the hole to the pulley.

Remember the nut is a left hand thread, so you will need to turn the spanner towards the nearside of the vehicle and it should come undone. (Clockwise looking from the front)

After it is loose, you should be able to undo it by turning it with your hand, once it’s off withdraw the assembly between the cowl and engine, ensuring you don’t damage the fan blades.

Once removed, Place the hub on the ground face down, and you will see four 10mm studs,

Remove these. Loosen each one and then fully remove once they are all loose.

Now you can remove the fan blades from the hub, and place it onto the new hub.

When you put the studs back in, put a little thread lock on them to prevent the studs coming loose.

Tighten the nuts and then put it into the engine compartment, the same way it came out. Do not damage the coil spring on the front.

Hold the nut in line with the centre of the pulley, and hand turn it, top towards the offside ( Anti-clockwise looking from the front). Feel the nut biting onto the thread and tighten as much as you can by hand.

Once tightened, again with the 32mm spanner and the bar holding the pulley, tighten the fan hub nut until it is tight. An all is done. Ensure all tools are remove from the engine bay, and there we are.