On Tue, 18 Nov 2003 21:24:25 -0600, "RB"
wrote:


I've been told that the o/bs, in general, lose maybe 1-2% of their power per
year due to normal wear. If this is so, and is factored in, then the power
attained at full throttle, the duration of the test run, and the load
imposed are all good gauges of the overall condition.

Some sellers, of course, won't be bothered with letting me do a dyno run on
their o/b.

If you can't do a seatrial, I think a dyno test is a great idea. I
also think, no matter the results, you bear the cost.

I recently bought a Yamaha 130. I new there was a problem, but unless
it was under load, all appeared fine. I took it to a Yam dealer and
until he put it on the dyno, it appeared to run fine. On the dyno, it
showed it was only putting out about 70%. I had the carbs cleaned and
then it was put back on the dyno. The dealer reported the engine was
putting out a full 130 hp. My on the water test sure made a
difference.

bb