Honda 200hp service and winterize. Gear lube, oil change, fuel and engine winterize. 

I've been using Mobil 1 in 2 sets of Honda outboards 1 has around 2000 hrs the other 1500 with no problems and very good compression. Had a very good Honda/ Yamaha tech tell me he thought Mobil 1 was better than anything else because of its sticky lubricating qualities and it's ability to withstand water and fuel contamination. Also found this; The corrosion control additives in motor oil are zinc and phosphorous. Both have been ramped down over time in automotive oils because they damage catalytic converters as engines wear out and begin to burn oil. They are still present, just at lower levels (diesel rated oils still have higher levels.) However, being a nerd I sent off a sample of Suzuki branded FC-W 10w40 synthetic oil to Blackstone Labs for analysis (they test oils for trucking companies to see how engines are wearing.) A buddy did the same for Yamalube 10w30. Short answer... both of them had the same zinc and phosphorous levels as your average automotive oil, and the Suzi oil was pretty weak in other anti-wear and detergent additives. Mobil 1 will have the same level of anti-corrosion additives that we found in Suzuki and Yamaha FC-W oil, and as good or better anti-wear and detergent additives. So will plain yellow bottle Penzoil or blue bottle Chevron. Yamaha, Suzuki, Mercury, Honda, etc... do not make engine oil. They source it from a supplier to meet minimum specs at the lowest bid, then bottle it under their label and sell it through their dealer networks for a large markup. It might be good to buy it to support your local dealer, but it isn't anything special in terms of protecting your engine. You can see my lab results here: www.arimaowners.com/gallery/6/4-250215150438.jpeg Yamaha results here: www.arimaowners.com/index.php?action=dlattach;topic=8580.0;attach=12975;image Compare to cheap yellow bottle Penzoil: www.pqiadata.org/Pennzoil10W30.html

Usually cleaner and often faster.