I was changing the oil on my Toro Timemaster and measuring how much oil I've been actually putting in and it seems like 13 Oz is the sweet spot. In the manual it states that the machine takes 20 oz. How am I able to drain the remaining 7 oz. Am I doing something wrong? I thought you just tip over the machine and drain out the oil after the machine is hot. I usually cut about 10,000 ft of grass and then change the oil to make sure everything is nice and warmed up.