Clarky130

New Member
Anyone know what size the viscous fan nut is on a '97 diesel? I've searched, but answers appear vague, with both 30mm and 32mm being quoted. I know it's smaller than 36mm, as I have a VC spanner that size...??
 
Ok, I cannot shift this frickin' viscous fan nut. I'm 'sharp tapping' away all I can on the spanner (yes, the 'wrong' way for the left hand thread) and all that happens is the belt tensioner 'bounces', the belt loosens and the pulley slips.

Tried jamming various things of various shapes and sizes between the water pump pulley and the belt, the belt and the tensioner, the pulley and the crank pulley... Nothing works!

I've given up for tonight and just given the nut a blast of PlusGas - I'll let that soak in overnight, but expect it won't make much difference...

How the hell do I get this thing off???
 
big long pry bar use it to lock the pulley by wedging it between the bolts that hold on the pulley so you can lever against the rotation from the fan spanner on nut.
or hammer and log chisel on the nut!
 
big long pry bar use it to lock the pulley by wedging it between the bolts that hold on the pulley so you can lever against the rotation from the fan spanner on nut.
or hammer and log chisel on the nut!

Tried the prybar on the bolts trick... Bolts are just too small to get any real purchase on. This thing is on bloody tight, and I'm not keen on the 'chiseling' route - don't fancy buggering up my water pump bearings!

I'll have another go later today and see if that plusgas I put on it last night has made any difference.
 
Once upon a time I wasn't paying attention and I removed the belt before removing the viscous fan, which made it spin freely since it wasn't constrainted anymore. What I did was to pry a large flat scredriver between two of the water pump bolts. It then came off with no problems.
Every other time I took out the viscous fan (with the belt on) it came off easily with a sharp tap with a not so big hammer.

Hope this helps :)
 
I have come to the conclusion that absolutely nothing on this earth is going to get this thing off. It simply refuses to move. I can hold the pulley still with a big screwdriver between the bolts, but the viscous fan nut will not budge, no matter how hard I hit the spanner or how hard I try and turn it.

Since I have now pulled a muscle in my elbow trying this, I'm going to sit down and admit defeat....

Are we SURE this thing is a left-hand thread???

Is it a nut that screws onto a thread sticking out of the pulley shaft? Or is it a bolt, that screws INTO an internal thread in the pulley shaft? Reason I ask... I might try heating it with my mini-blowtorch, see if that can help shift it. I would need to heat the right bit, though...
 
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I have come to the conclusion that absolutely nothing on this earth is going to get this thing off. It simply refuses to move. I can hold the pulley still with a big screwdriver between the bolts, but the viscous fan nut will not budge, no matter how hard I hit the spanner or how hard I try and turn it.

Since I have now pulled a muscle in my elbow trying this, I'm going to sit down and admit defeat....

Are we SURE this thing is a left-hand thread???

Is it a nut that screws onto a thread sticking out of the pulley shaft? Or is it a bolt, that screws INTO an internal thread in the pulley shaft? Reason I ask... I might try heating it with my mini-blowtorch, see if that can help shift it. I would need to heat the right bit, though...


You're not holding your mouth right when you hit it. Large nut at back of fan. Fans always undo in the direction they rotate. In your case clockwise
looking from front of car. It is a doozel isn't it? If not tuther way. If it really is that tight, only thing that will shift it is shocking it with a cold chisel.
 
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I just use a long cold chisel and a block hammer. Never fails. Mind you there are a few here who will call me a butcher for such an approach.
 
Job done! The blowtorch trick worked... Still needed a hell of a shove to crack it loose, though.

I now have a fully-functional viscous fan unit surplus to requirements... If anybody needs one?
 
Job done! The blowtorch trick worked... Still needed a hell of a shove to crack it loose, though.

I now have a fully-functional viscous fan unit surplus to requirements... If anybody needs one?
I always undo viscous fans with a cold chisel and a sharp crack, never ever had any issues with water pump damage(Done hundreds I look after a fleet of around 100 Transits and you had to take the fan off to do the timing belt on the old shape trannys). I personally would not use a blow torch as I would worry that heat transfer from the nut into the water pump would do more damage to the bearings. How did you do it up? Again I always do it back up with a sharp crack on a chisel, I have seen first hand what happens when a viscous fan comes off, radiator, cowling, fan, bonnet dented, that sort of stuff. Before you ask it was not a fan I had left loose it was a shot bearing in the hub and the whole lot parted company at speed.
 
I always undo viscous fans with a cold chisel and a sharp crack, never ever had any issues with water pump damage(Done hundreds I look after a fleet of around 100 Transits and you had to take the fan off to do the timing belt on the old shape trannys). I personally would not use a blow torch as I would worry that heat transfer from the nut into the water pump would do more damage to the bearings. How did you do it up? Again I always do it back up with a sharp crack on a chisel, I have seen first hand what happens when a viscous fan comes off, radiator, cowling, fan, bonnet dented, that sort of stuff. Before you ask it was not a fan I had left loose it was a shot bearing in the hub and the whole lot parted company at speed.

I didn't do it back up, I'm permanently removing it because I've done the Aircon Fans mod. Engine runs at exactly the same temp as it did before with no issues - haven't even had the ac fans cut in yet.
 

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