As above its not the pipes and its not the o'ring that sits underneath the resiviour coz ive had that replaced.Anyone know where else it could be coming from,a small bit of fluid gathers on the block below the resiviour and next to the pump itself.Causes nasty smell and bit of embarassing smoke!

 

if the pump/bearing is too badly worn then the oil can leak through past the shaft.
This can be caused by an over tightened belt or wear through age/use.
The oil would then come through behind the pulley.

You can try to move the pulley to check for play but you might need to slacken off the belt first.

 

There are 2 O' rings on the power steering pump res, one is under the cradle the res is bolted to, and the other(which you have possibly replaced) is on the stem at the end that you push into the pump. They tend to both go at the same time due to the heat the pump and engine produce. Another thing to check is the power sterring pump engine sensor, you can easily see this as it's the only wire going into the pump and if memory serves me well, as you're looking down on the pump it'll be on your right side, get someone to put the steering on full lock and check if any fluid is squirting out. If it is then you have to take the pump out and replace the wire along with the gasket, not a hard job and you can defo get the wire and gasket from your local subaru dealer.
If it's only a little fluid, then most likely it's the O' rings, one thing to note is that the one on the end of the stem looks like it's ok, but it's not as it'll be rock hard and not doing it's job of sealing the hole. Go and get some different sized O 'rings from your local hardware store anything from 10mm-30mm then you should have the size you're after.

Hope this helps

CRAFT

 

Thanks to both of you thats a great help.Ill get it sorted this week