I already checked the radiator for oil, (drained and refilled while I was there), and check the dipstick for brownish oil. No oil in the radiator and the oil on the stick looks fine. The oil was dark but I have put alot of hours on it this year, but not brown or frothy. Last year I was faithly putting lucas diesel treatment, this year I got away from it. I hadn't run the tractor much in the last two months and actually due to Katrina, it hadn't run at all in the last 30 or so days. I started it up a few days ago and it stuttered and stalled, that when I noticed quite a bit of water in my filter. I since have added new diesel filter and lucas treatment. Thanks again and I continue checking the oil for water, vis versa.