I am a Merc guy. I have been since I was a kid, and continue to be today. I am a fierce nationalist and Mercury Marine is the only US-based outboard builder left. That being said, I do not personally care for the Mark 6, Mark 6A or the very similar Mark 5. They are GREAT running motors and have a lot of speed for their size. But they require a tanker-truck load of patience to work on, compared to OMC stuff. If you want to know why some people hate Mercurys, you will know after you work on one of those.
In particular, as Jerry says, a HUGE, HUGE problem with them is that they will tend to break off a small ring of aluminum, at the aft end of the gear case bullet, just in front of the prop. If the ring has broken off and has been removed, it is hard for the unknowing person to tell the difference. However, this makes it so there is virtually nothing left to hold the guts into the gear case. And since it is a common problem, replacement cases are hard to come by.
Again, though, not to be a total negative Nellie, they ARE good runners when done. If you buy it, though, don’t pay a lot. A really nice one with a good gear case is worth a couple of hundred. A so-so looking one with a broken gear case is worth almost nothing.
Long live American manufacturing!
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