I have a 2004 120 hp mercury force, it has run well all summer than when cruising at almost full throttle out of know where a sudden loss of power and putt puts also seems to choke out when trying to go faster than say 10 mph. I asked a marine mechanic to look at it and he said there was water in my gas. I put in a fuel water separator, new plugs and stabilizer in the gas. I still have the same gas in it but with all the work mentioned above. Today we tested it for a couple hours the same thing was happening, then for about the last half hour it stated to come out of it some. I was running up to about 30 mph some of the time but every once in awhile it would start acting the same and then come out of it, at least with out the putt putt for about ten minutes at a time. It usually tops out at about 45 mph and with a lot more jump from the start. I was hoping you may have a few answers for me.