o/b running issues - when warm

External Since: Jul 11, 2005 Posts: 6

I have a 200hp Suzuki O/B with 3 Mikuni carburettors; all was well
until a recent service.
Now o/b starts perfectly and first run will go superb, when we stop to
change over skier/driver, typically 5 min or so stop, that is when
problem occurs.
The motor restarts OK, but when you engage gear still OK, but as you
open throttle the engine does not pick up, and usually stalls.

The simplest way is to recover seems to be:
a) engage gear and idle away at low speed for a minute or so, engine
then gets to a point where it sounds less lumpy, and it will then run
OK .... A quick 30sec run around and it will be OK to then return to
skier and do an immediate deep water start with no problems. (i.e. no
powering off engine)
b) start engine, and use fast idle lever to increase idle speed to
about 3.5 to 4k revs, do this for about 20 secs ... and again it will
clear and run OK.

This seems to me be something like choking up due to mixture incorrect
..... But why would the first run go so well?

Anybody any ideas? .... I will be taking it back to service agent, but
be good to have some ideas.

Rick

External Since: Jul 05, 2005 Posts: 9

As part of your service they may have adjusted carb mixture while
running in a shop test tank or on a hose. Test tanks are ok but not
failsafe. I would suspect mixture is too rich on one or more carbs. It
may run well on first start as a cold engine tolerates a richer
mixture. I would expect the dealer to prove the repair to me by
offering an open water test ride after the repair. You can then prove
it out under actual conditions.