Mk1 and MK2 viscous fan

[Rackned]

Because of the lovely summer we are having my engine has been running a little bit more warmer than normal.

I’ve decided to look at ways to keeping it cooler in hot conditions as it’s fine in cooler normal English days. The first thing is obviously the radiator second is a electric fan but before I do that I am looking at the viscous fan and not sure what differences there are between the Mk 1 and the Mk 2, I have a Mk1 car.

there is a vast difference between buying a conversion kit and just a viscous fan unit, so I’m looking for some advice as to what I should do and secondly why is it that you have to convert ?

Also I have already flushed cleaned etc and done most of the common things associated with as a heating problem, the car gets to about 120 on very hot days 90 on cool days and I want to avoid the top end.

Mark

[Jeff]

Took mine out twice in this weeks heat and temp gauge stayed the same as normal. thermostat sees to that.

Elec fan never cut in.

[Si5]

Mine has been running hot since I bought it 4 years a go it's a MK1 with a MK2 rad. Through looking at forum noticed that best way to fill the system is from the top screw on the radiator. When I opened this saw actual water level was only to the top of the expansion bottle and whilst I have read this before never really sunk in.

Levels now topped and running very well even in the recent heat. May be of some help

Thanks

Si

[Rackned]

Well Due to weekend odd jobs, I didn’t start work on the car. So will be looking at next weekend. In the meantime I await any advice on the variation Mk1 and Mk2 if anyone has such TiA.

[DJT]

They both do the same thing: allow the fan to rotate at engine crank speed until they reach about 2600rpm when the viscous fluid shears and they freewheel, reducing power sap and noise.
Mk1 couplings have studs to which the fan attaches. Mk2 attaches by means of bolts through the coupling. They were manufactured by Holset of Huddersfield, but neither have been available new from them for many years. The Mk1 type is not available new from anywhere as far as I’m aware. The Mk2 type, TKC101, is used on other vehicles such as Land Rover (under part number ERC2849), so is remanufactured. Aftermarket ones are available from Stag suppliers fairly cheaply, but genuine Land Rover ones are far more expensive. Rimmer Bros sell both, one at £72 and the other at £237. Make of that what you will, but the last time I needed one (about 11 years ago) I bought a TKC101 and it failed after a few months. This was replaced under warranty and failed again. I sourced a ERC2849 from a govt surplus outlet and it is still fine after 10 years and 35,000 miles.
As for the conversion kit, this includes a new coupling, new fan and bolts. At Beaulieu today Tony White (tonywhite on here) had several used but good Mk2 couplings and fans. Might be worth contacting him 07830 226461.