Pros: The motor is powerful and smooth above 2000rpm and better economy than I expected.
Cons: Occasionally hard to start and does not troll well.
I would just like to start by saying that I am writing this review from Australia for whoever is interested.
I shopped for about 12 months before buying a boat and motor package because when I purchase anything I normally keep it for a while, and finally my pocket dictated. The mercury 90hp saltwater series is one of the less expensive motors on the Australian market at $8000 Aussie dollars at the time of purchase.
I have only had the motor for 12 months and have had no problems. The motor only has 60hrs running time and that has been all in saltwater.
Cold starts are a little hard at times, although once warm the motor starts OK, usually first go. There is some vibration at low rpm but is smooth above 2000rpm right through to 5600rpm at about 44mph according to the speedo. The 90 Mercury is pushing a 18ft alloy bowrider by no means a heavy boat.
There is gearbox rattle under 1000rpm which I've been told by the Mercury service dept is attributed to by the stainless steel props weight. This noise is annoying but I generally don't stay in that rev range for long and I've heard that there is a fix for it which I'm planning for next service.
I generally travel at 3500rpm to 4500rpm were the motor sounds most comfortable, above the 4600rpm the motor is noticeably noisy but from what I hear that's normal. The motor used to stall when I first got it but generally started first go there after. Mercury service dept said the motor is proned to stalling during run in but I'm not to sure about that.
I have been impressed with the motors performance one time I had the boat heavily loaded taking some friends to a camp site and was amazed with the motors performance not feeling the additional weight at all. At a quick calculation I would say there was approx 1400 kilo's. Not sure what that equates to in pounds. I also have a tube which my kids enjoy riding behind the boat and the motor has made little effort of pulling them around on it. I haven't tried to ski yet but that is next on the agenda and I'm sure the motor will do it with ease. The motor acceleration is great you can really feel the kick back when pushing it and although noisy up high it sounds like the motor is growling and can sound good if you are a rev head. Economy has been better than I expected getting about 7 hours to the tank of 100 liters.
The 90hp Mercury has been great so far. I will probably write another review 12 months down the track and tell you more, but for now I can recommend the motor but if you want a quiet motor buy a 4 stroke.