I have a 1996? 753, that I've owned since about 2000. 3500 hrs, in pretty nice condition. The right hand drive motor is seeping oil quite badly, right through the cast cover that you see when you remove the access cover. I've already replaced this part years ago, after trying to weld the seeping area, it would stop for a while and then start seeping in a new area,. A pretty good old local welder blamed it on a porous casting, but why would I get another? Is this somewhat common or just my rotten luck? It's getting to be a pretty fast leak, enough to be messy on the shop floor all the time. Any input is greatly appreciated.