i'v noticed that the crankshaft pulley that the timing belt runs on has been rubbing against the block and there was a bit of metal filings around the oil seal.
does anyone know what mite be causing this?

Cheers

 

That obviously should not happen. The crank can move axially if the thrust bearing in the engine has worn, and that movement allows the pully to touch the block and hence the metal deposit.

The thrust bearing resists the pull of the clutch when pressed.

It all sounds like your engine is a high mileage/traffic use engine?

 

yeah i'd say it has a lot of traffic use, but the mileage isnt all that high.

would this crank movement be of concern to anyone especially if i was planning on getting a power fc and custom map very soon?

 

I would fix your thrust bearing problem first mate as it will only get worse, if the trusts fail completly you will end up with serious engine damage and tuning an engine with internal problems is never a good idea.

 

Too true.
If the thrust bearing gets very thin
1
You have an engine full of bearing metal floating about
2
The side faces of the connecting rods will touch the crank webs and worst still will be tilting the rods off center.
= total failure.

First though, check everything for tightness and the crank end float.
iirc it should be max 0.5 to 0.7 mm (best check first)