I am working on a TO30 that has been plagued with oil building up in the combustion chambers. I put in new oil guard seals on the intake valves but that did not help, so I pulled the head. I found that the pistons were installed with the word "front" and arrows pointing toward the back of the tractor which puts the T slots and oil holes on the wrong sides. The pistons and sleeves look OK (like almost new). I am thinking about honing the sleeves and putting the pistons in correctly with new rings. Seems like backwards pistons might be the cause of the oil fouling. Anyone with some experience care to comment? Thanks.