2001 merc optimax 225 horse,(370 hours) seems a little low rpm in neutral and stalls when putting in gear (ie when nosing in to dock), but runs great. When restarting has a small high rev before idling, then might stall again. Runs great once you get past that little high rev. Any suggestions?
Faulty throttle position sensor should give a visible and aural fault.
Could be the shift interupt switch is hanging up, but I would not expect it to stall after restarting.
Some air in the fuel (like starting after not running for awhile) causes my 135 opti to act like that. Squeeze your primer bulb when it happens to see if it has gone soft (air in the system). Check all you fuel line connections.
Iain Pelto
Edgewater 185CC “Jumpin’ Bean II”
If you are getting good fuel and all that…might be that the idle timing is off a little. If you have to advance the throttle/timing to re-start, it could probably be adjusted towards better performance.
Chris V taught me that one on my Merc(40HP) 
Timing is not adjustable on an Optimax. Everything is done by the ECM
Iain Pelto
Edgewater 185CC “Jumpin’ Bean II”
start with the simple first
battery voltage at the motor
low voltage at low rpms will make an optimax do some very strange stuff
I’m now at www.teamcharlestonmarine.com
quote:
start with the simple first battery voltage at the motor low voltage at low rpms will make an optimax do some very strange stuff
Very true, that a good one to check. The Optimax engine controller and injectors at idle actually use as much or more power than the alternator can produce. So if you have a weak battery or bad connection the control system can become starved for power dropping the voltage which in turn causes erratic fuel injection or stalling.
Iain Pelto
Edgewater 185CC “Jumpin’ Bean II”
i was having the same problems with evinrude DI’s. Did a decarb and that solved the problem. Never hurts to do a decarb anyway, might be worth a try