Our 42 is hull # 215. I use Dello 400 30 weight oil and it takes about a gallon and 12. The transmition takes the same oil and two gallons will cover changing both. As far as the oil filter goes, you can either get one from Yanmar or use another brand from an automotive store. I use a Purolator L 24458 and have never had a problem. Their is not drain plug in the Yanmar so you have to pull the oil out the dipstick. Also the oil filter is very tight along the starboard side. What I've done to keep from dumping oil in the bilge is to use a screw driver and punch a hole in the side of the filter facing up. I then suck all the oil out of the filter through the hole. Cover the hole with duct tape and then take if off. You still may drip some oil, but you can catch it with a couple of paper towels. Good Luck.
