Can Anyone Tell Me Which Way The Not So Viscous Fan Unscrews? And What Damage Is Likley To Occur When A Cambelt Snaps?
(Cos Yes...You Guys Were Right, Seems To Be Cambelt That Went)

The opposite way to what you'd expect. And it can be a bitch to remove.

There is a proper spanner available but you might be able to manufacture something from an old spanner or cheepo and bend it to fit, failing that use a drift and a tapometer.

the turbo diesel is the same as the N/A! One big bolt holding the plastic assembly to the backplate which unscrews anti-clockwise as usual and then four little bolts which also unscrew anti-clockwise. That should be all you need to remove fanwise to get the timing cover off. Just hold the fan tightwhen you're trying to undo them. You might have bent some push rods (couple of quid each) or at very worstbent or shattered a rocker arm. Not too big a deal.

-Pos