Neal, I had a 1988 R50 with the Deutz engine. Previous owner had complained about excessive oil consumption and the engine had been apart after the first season. In the beginning, we thought it was using quite abit of oil, but in a sporadic manner, ie 2 litres today, non tomorrow. Finally discovered that a) ignore the level on the dipstick when you pull it first time in the morning (check a second time) and b) the level stabilized at halfway between full and add and would hold there for 50 hours. Same engine in a 9150 DA tractor doesn't use oil.