just take top half of timing cover off and if theres oil on the belt, you know its a seal.... you will have to replace the belt as oil weakens the rubber and you risk it slipping, Got mine replaced, cost 20 euro for both oil seal and crank seal.. got a lad to do it and he charged me fuck all really... you dont need to remove engine, once you get the alternator belt off, remove bolt holding on the Pulley, drain oil, take pully off..take off timing cover, and remove timing belt...you can take the old seal out but prying it with a very narrow screwdriver or tap it with hammer and chisel, being careful not to chip the block, the slide new seal into place and you can put old seal infront of it and tap it with a hammer until it is in fully... then set the timing correctly and put new belt on, then reassemble and put new oil in..