Hi guys, I'm getting prepared ahead of time to do the yearly maintenance/winterize of my Sundeck 200 2006 when we get close to the end of the season. Is the first time I am going to do it so I am getting all info and creating a checklist. I have 2 Service Manuals and I still not sure which one is the right one for my engine (Mercruiser 5.0 EFI). I have the Service Manual #24 and the #31. The pictures in the #31 looks more like my engine. Serial number of my engine is: 0W351348. In the part I am stuck is the step of add 2 cycle oil to the gas system for "Long Storage/Cold Winter" because the Service Manual #24 says: "b. Remove the water separating fuel filter. c. Pour out a small amount of fuel into a suitable container, then add approximately 2 fluid ounces (60 ml) of Quicksilver 2-Cycle Outboard Oil to fuel in the water separating fuel filter. d. Reinstall water separating fuel filter." bu the Service Manual #31 says: "1. In a 23 l (6 U.S. gal.) remote fuel tank mix: a. 19 l (5 U.S. gal) regular unleaded 87 octane (90 RON) gasoline b. 1.89 l (2 U.S. qts.) Premium Plus 2-Cycle TC-W3 Outboard Oil c. 150ml (5 ounces) Fuel System Treatment and Stabilizer or 30 ml (1 ounce) Fuel System Treatment and Stabilizer Concentrate. 6. Start and operate the engine at 1300 rpm for 5 minutes." So, as you can see one manual says to put a little bit and the other one to use a lot for a long period of time (5 minutes). Makes sense for me the step of the 2 cycle oil to prevent corrosion but I never heard about a gas/4cycle engine be running on 2 cycle mix for 5 minutes and that kinds of scares me. Is not the same 2 ounces of oil than 2 qts, huge difference. What do you do? or which manual I should follow? Can I damage a gas engine running on 2 cycle mix?