thats a coolant pipe, not oil.
to replace the orings, you need to pull right side (clutch cover) off. there are 3 orings I believe, 2 on top, one bottom, but there may be 2 on both ends.
you will need to drain oil and coolant to do the job. be very careful reassembling, as its easy to cut the orings, or get them improperly positioned.