If it looks like creamer that you pour in your coffee it is most likely water. BUT, I've seen perfectly good gearlube get very close to cream color. If it has a tint of yellow or off white it may be fine. It sometimes happens if you switch gearlube brands or chemistry or the lube just gets aerated and changes color. If you haven't already drained it, just let it sit for several days to a week and check again. The water will separate and drain out first when you open the bottom screw. Or as Bruce suggests, drain it in a mason jar and wait for it to separate. While you're waiting for it to separate, pull the propeller to make sure that no fishing line has wrapped around the propeller shaft and invaded the seal area. This is normal PM anyway. Grease the prop shaft with good marine grease (do not use Never Seize) and reinstall the prop.