Walter wrote:
If you just had it changed 3 hours prior I think you'll be ok, you just don't want to winterize an engine with 30-40 hour oil in it due to contaminants and moisture just sitting on all of the internal surfaces like the bearings for extended periods of time. The main reason is to get rid of the moisture in the oil.
I know the operating temperature on my boat is lower than most cars (162 versus about 190), but I'm really surprised to read this kind of concern. I grabbed some oil reports from a couple of track cars while I was at work today, and in each case, the water content was <0.1%. Fuel dilution was equally low. I'm wondering what an oil report would look like for one of our boats. Usually the oil breaks down by continued shearing of the long polymeric additives that improve viscosity. Maybe I'll grab a sample and send it off to Blackstone next time I change the oil.
Having said that, please don't take my comments as dismissive. I've got an automotive background, but I have come to realize boats are a totally different animal. I've been assuming I can just drain the coolant out of my boat and be on my merry way until March.