What kind of problem are you having??
An 8 HP sailmaster is a darn good motor and well worth fixing, or replacing with another good used one. In the late 80's they began using a fuel enricher that operates as a choke, rather than a real choke. Why I have no clue, but it operates by putting extra fuel into the engine. The o rings inside them fail and they will leak internally, making the motor run very rich, smoke, no power. Also, the fuel pumps on outboards dont last so long, and not long at all depending on your regional/local fuel formula. A weak pump, coupled with a leaking enricher can make the engine almost inoperable. The parts to spiff it back up are less than $30 and are quite easy for a DIY to replace.
In addition, carbs can get clogged passageways and cause poor idle, no idle, hard starting, wont start, etc.. Again, quite simple, parts are cheap. Disassembly and flushing with a blast of carb cleaner will usually correct them with no parts required.