Well, I guess it depends who you ask. I, personally think this vintage of these engines are great. This year engine (please make sure it is a 79-not some other year) has the nice CD ignition and the simple/reliable metal bowl carb. The powerheads and gearcases on these engines are very rugged, they can take a beating and still work well.
Now, for the not so great things. Is this a salt water motor? If so, there is a $2.00 upper water tube grommet that creates a cooling blockage that is labor intensive to repair. The upper motor mounts should be checked as well, that is a big/expensive job. The lousy plastic pieces parts, especially throttle related are expensive and prone to wear/poor repairs.
Like anything else, you should do all the normal inspections prior to purchase. Any signs of overheat on the block, is the white paint discolored badly/ignition wires/harness melted to block? Do a compression test and check the gear lube for freshness/lack of water. Any broken/bent castings? How much do they want for the engine?
Feel free to post pictures, along with the model number if we can help further.
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