300tdi rocker cover gasket leak? (with pictures)

Hey folks not sure if its my rocker gasket thats leaking or not.

If you look at the picture with the red arrow is a hose and its got some red electrical tape with a clip over a small hole a few mm (iv kind of left it for far too long now, other problems to fix as well!:lalala

But the enginge is getting quite wet with oil and its all round the rocker as the pics show.

Im not the best diy'er but i think il set the valve clearances and replace the rocker gasket, but can someone tell me what this hose is called so i can order one up or will any old bit of tube that fits do???

Cheers Mike

See here: http://www.landyzone.co.uk/lz/f49/crankcase-breather-pipe-diameter-160850.html

The hose swells, looks like someone has tried to botch it. I replace mine with some 3/4" straight hose but it has kinked a bit but seems fine.

cheers yeah it was me that botched it thought it was best to "fix" it when i noticed it an never got round to replacing it!