I have a 2003 Johnson 140 and I have about 10-12 hours on the motor.I was going to change the oil for the first time and was wondering how difficult to get to the oil filter....looks like 6 screws for that lower cover.Also I was thinking of using Mobil 1 15W-50 Synthetic.Is there anything else the Dealer does for the 10 hr check? I would like to do this myself. You sound like you really know your Suzuki/Johnson 4 strokes....Thanks for your help