I did the first oil change on my new mower with a Kohler Courage Pro 25, (12 hours) and it scared the crap out of me. After coming to my senses and realizing it is an air cooled engine, and not anti-freeze in my oil, I was baffled and slightly confused. The color of the oil that came out was a butterscotch with a hint of green. Does anyone know what causes that? Should I be concerned? This mower is a brand new Toro Titan Z 60" - yes its a residential mower. The dealer talked me into it due to the 3 yr/340 hr warranty, and that it was aimed at starting LCOs. It has been a POS for the couple of accounts that it gets used on (that's another thread though!), and if this is an engine problem, I'm going to end up at the dealer extremely angry - with it on the trailer - and hopefully trading for a Z Master 60". The only thing I can think of is that it is water in the engine, or maybe an assembly lube, since it is the first oil change. I store the mower inside a garage, and has only been on the trailer once in the rain during its life. Anyone have any feedback on this?