Where is the oil going? No smoke. No leaks.

[nepa]

I was given an old Craftsman 11 HP lawn tractor that had a bad engine knock due to a leaking carb that filled the crankcase with gas. I bought a used engine for $25 and replaced the knocker I had to use the old muffler because of size and the old carb because of choke differences. I rebuilt the carb and it no longer floods the crankcase. The replacement engine runs really well. Absolutely no smoke and no signs of leaks anywhere. Bit still, after running for 10 minutes, the dipstick reads about a pint low. It baffles me as to high oil consumption with no signs of where it is going. I have not looked at the crankcase breather and do not know what to look for there. I figured that if the breather was the problem of so much oil consumption that I would see smoke. One clue might be that although I do not remember the condition of the foam air filter when I first put it on, but when I took it off yesterday, the foam seemed to be too heavy with oil (which I then removed). I do not see how the oil would travel up hill to the foam filter anyway and, of course, the crankcase breather is well down the carb so that is not likely to travel up to the filter. Any suggestions?