CAVE engine sudden increase in oil consumption but has perfect compression?

[FlexibleMouse]

So I noticed a few drops of oil on the drive today. Turns out I have a large oil leak that has been going on for some time. It appears to be leaking from the gap between the gearbox and the drivers side driveshaft. The oil is a mix of old baked on crap and brand new still golden. What I don't understand is why it appears to be coming from the gearbox, surely the engine and gearbox don't share an oil circuit? or could it be the leak is dropping directly on that spot from above? anyone have any ideas?. 

 

I have no doubt that the engine is burning oil, but this leak has to be a big contributor to the consumption. I'm going to deal with the leak  and see what happens to the consumption before I do anything else.

 

Edit: actually it's probably the rear main seal...

Edited 24 June, 2019 by FlexibleMouse

[Kobayashi]

on the plus side now you know its a leak it should be relatively easier to sort out the leak first, & clean what is gunked up