40-60 Merc Mods
The purpose of this wiki is to spread and retain knowledge of Mercury 59" 3 cylinder outboard motors.
For The People
Size Matters
59 inch motors began replacing 52 inch motors around 1997 and were badges as 40, 50 and 60 HP. They were produced until 2005 although you could get them in 50HP configuration up through 2009 until their EPA emission credits were finally consumed.
59 cubic inches = 966 cc (0.966 Liters)
Round Cowling
The image to the left is what's considered a round cowling 3 cylinder. It would be badged as either 40 or 50 HP and contain the 59 cubic inch block.
The motor in the picture is a long, 20" shaft. The proportion of the cowling suggests that it's a 3 cylinder and the distance between the first ventilation plate and the lower clamp mount mean it's a long shaft.
Square Cowling
The square cowling was almost exclusively a 60 HP engine. It was available with the Big Foot option and only electric start. The motor pictured has a long, ie 20" shaft, and is setup for remote steering.
Big Foot
The Mid and Lower on a Big Food engine are unique and of no practical use to high speed watercraft.
The zinc on the foot and a large bullet are indicators of a lower being Big Foot.
Old Stuff
The sticker scheme on these square ish cowlings to the left are a dead giveaway that it is not a 59" motor.
4 Cylinder
The ever so slightly taller cowling on the engine to the left is a subtle indicator that it is a 4 cylinder. The sticker scheme suggests that it is pre 1998 when 40 HP motors were only 2 or 4 cylinder.
2 Cylinder
The 2 cylinder 40 of the same vintage as the 59" 40 has a shorter cowling.
4 Stroke
This color scheme is too new to be 2 stroke. Also, 60's never came with a rounded cowling.