One is on side of block, the second is on top of valve cover. Both caps are marked "Oil". Does it matter which one I use to refill after oil/filter change? Dumb question maybe, but have a nagging doubt and no manual to refer to.
Can not speak for Kubota but on Kioti, there are two as well but should only use the one on side because the top one drains too slowly allowing oil to enter the breather tube from top of head pan to intake manifold. It would seem as the drain holes in the diffuser over the valve head are too small and slows the flow down to the block.