I have had 3 different Yamaha 9.9 HT on previous boats and they were brilliant. Quiet, efficient, no smell and real value for money
- engine, transmission
, stern gear
and prop all for less than £2000 GDP. If I could fit 2 on our current
boat I would - far better value than 2 Yanmar
Our last was on a 32 ft cat and a number of times we had to motor all the way to cross the English Channel
~70 nm @ 5kts using about 6 UK gallons. We also brought the boat up from the South of France
via the Canal du Midi to Royan entirely under engine, all day long at 4 kts for 2 weeks. The only problem we ever had was at the beginning of the season the engine would not idle properly, cutting out as you changed gear. Easily fixed by removing the slow running screw and blowing it out, probably fuel gumming despite draining the carb.
We had it set up so that the engine steered with the rudders when down (lifted when sailing). That made the boat 32 ft x 17ft 6in a joy to park and the high thrust prop really worked in reverse unlike previous 2 strokes which were less than feeble in reverse.
Apart from normal oil changes etc, I would run the engine in a big dustbin with fresh water
for about 2 hours at the end of the season and at the start to flush the waterways clear and dissolve salt
. Then take off boat and into workshop for the winter and oil changes etc.
It did provide some charge to the batteries, but that was a bonus and you do need alternative charging
for anything more than occasional very light useage. We had solar
so it did not matter.
All in all, a great bit of engineering.