E430 m113940 viscous coupling

[johnsco]

Changing the viscous coupling on the E430 looked a pretty-simple job.
(Bad mistake #1)
I guess the photos speak for themselves.

Someone has been there before me and has butchered the 36mm hex nut that secures the coupling to the water pump pulley.
I have given it everything I've got with the correct spanner and the correct tool for locking the water pump pulley.
Can't shift it

First question ... If I remove the four hex bolts that secure the pulley to the water pump flange, can I then lift out the pulley with the VC attached.
If so, I can then get it in the vice and remove it with some brute force and ignorance.

Second question ... It's far from obvious how the poly-V-belt is tensioned.
The owners' hand book is no help at all.
The Russian site shows a fitting diagram with 8 pulleys ... One of which is called a tightener pulley / sheave pulley.
Unfortunately, this car only has 7 pulleys and the tightener pulley is not there.

Any guidance would be warmly-appreciated.
Thanks in advance.

 

[johnsco]

BUMP ... Help guys please.
Even if it's only on the question of the belt tensioning.
I can take the rest apart easily and find out how it comes apart.

 

[BlackC55]

The belt tensioner either has a 17MM nut under it or a large female Torx. Its just to the right of the water pump.

I think you may have to cut that viscous fan nut off. It looks horrendus.

 

[johnsco]

Thanks BlackC55.
Horrendous it sure is.
My hope is to remove the bolts that secure the fan pulley to the waterpump flange, complete with the VC, and then to remove the nut with a cutting wheel.
Hence my first question.
Cheers
Johnsco

 

[grober]

The large nut is a left hand thread identified by notches on the centre of edges of the hex nut flats[ well would have been been before the " butchery"] see a different example below.
ps the new viscous coupling will come with a new captive nut so not to worry about the old one provided the threads are not stripped on the pump spindle. WHEN YOU GET THE NEW COUPLING MAKE SURE TO STORE IT IN A VERTICAL POSITION [ AS IT WOULD BE ON A CAR] NOT FLAT.

 

[johnsco]

Thanks Graeme.
I've got the replacement coupling from Franey (Good price on a Meyle part ... with a 2-year guarantee).
As you say, it has a new captive nut, so I can destroy the old nut as I remove it.
It certainly won't unscrew !!
I'll let you know how I get on.

 

[Iain430]

Replaced the viscous fan on my E430 and if i recall the nut was right-handed