Link to Mercury outboards serial #s, 9.9 hp to 30 hp. http://www.themarinedoctor.com/cgi-bin/YaBB.pl?board=MM;action=display;num=1137539563
i have a mercury outboard motor the serial# is G034632
Mercury outboard, 8hp, sn A721731 manufactured in 1987.
From what I can find in serial number tables, your outboard is made in 1975. My refernce: http://www.marinshopen.se/Hj%c3%a4lpmedel/Modellguide/Mercury/3565Hk/tabid/107/Default.aspx
Mid 80s
1987
A 40 hp Mercury outboard, serial number 5897057, would have been manufactured in late 1981.
1988
1985
what year is mercury 9.9 outboard engine serial number 9495587
If manufactured after 1965, an 80 hp Mercury outboard requires a 50:1 fuel, to 2 cycle oil ratio.
The "OC" model 75 hp Mercury outboards were manufactured in 1990.
The Mercury outboard 4.5 with serial number 4273176 was created in two type mode which are the "M" and "ML" model. Both model types were manufactured in 1975.