Your Merc 4-Stroke big foot is actually a Yamaha Technically. Mercury 115 four strokes and below were Yamaha's with Merc stickers basicly. That's why this year I'm on back order on about 10 mercury 4-strokes since Yamaha won't supply Mercury anymore since they got into a dispute last year.

You should run fuel stabalizer in your boats year round. Gas these days is poor in quality and with boat motors being a lot more technical than they used to be the fuel is really messing up engines these days. We see more engines running bad do to not running Stabill.

Engine wise, Yamaha is probably the best on the water, Honda is a good engine as well as everything else. The only one I can't say how it is is Evinrude. We've only sold a few the past couple years and they seem to be great motors, but I've not sold enough to form an opinion. We sell Yamaha and Mercury about 120 per each year brand new and they both run awesome, but the Yamaha seem to be a little less problimatic.

Matt