Many early model, smaller hp Mariner outboards were manufactured by both Yamaha and Tohatsu. These models were of different design than the late model engines. This may be the problem.
A 150 hp Mariner outboard, serial number OB199335 would be a 1987 year model.
The 150 Mariner Magnum II outboard motor with the serial number 6481693 was manufactured in 1993. Mariner outboard motors typically use a serial number system that can help identify the year of production. For precise information, you might also consult the manufacturer or a service manual.
Along with the engine serial number, the horsepower rating is needed to detemine the year model for a Mariner outboard.
1956
A 9.9 hp Mariner outboard, serial number OC269812, would be a 1990 year model.
1998
1991
1990
What year is the mariner 9.9c 682cs 066674
One manual has the number 6263906 listed as a 1983 model
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