"Sailman" wrote in message
om...
I am considering buying a boat with an old (c. 1975) 115hp Mercury
outboard. According to the seller, it was rebuilt about 300 hours ago
and runs great. Assuming the basic checks came back fine
(compression, lower unit oil, etc.) and that it was rebuilt by a
reputable place, is an old but recently rebuilt outboard a good idea?
Put another way, is a 300 hour rebuilt engine comparable to any other
300 hour rebuilt engine, or does the old age add significant negative
issues?

Also, any guess as to the value of such an outboard?

Finally, is there some natural limit to the numbe of times you can do
a major rebuild on an outboard?

I once bought a boat with a 115 Merc attached, I think it was about
a 1984 engine. The engine ran fine my first season. When I put her in
the water on the second season it worked for 10 minutes then the
shaft running from the engine to the prop broke. From everything
I could find out it seems we would have had to take the engine
compleatly apart to fix the shaft.

Anyway, here's my point/advise: Even if compression & all else looks
good and it runs strong - any engine can break in a major way. And older
engines are more likely to break with major problems. ~ As for the
rebuild: as another poster said, you don't really know what was rebuilt.
Even if they repaired everything else, some one major part (like the shaft
in my engine) could still go.

Another way to consider this: Say something major DID break. Something
big enough that the cost to repair was not worth it. Then what would the
boat be worth?

Good luck.