250 XS Optimax Engine shuts down when The Tilt/Trim, Jack Plate is used

[rwlufkin]

I have a 2009 Mercury 250 XS Serial #1B792272. Anytime I use the T/T, Jack Plate or Power Poles it kills the engine or it will stumble. Also it will not rev past 3400 rpm. I can disconnect the battery and it hit 5600 rpm until I get a over charge alarm. I have swapped alternators hooked up a seperate battery and cables to the engine and the problem still exists. This boat has been to several shops with no luck at all. Thanks, rw

[PanRonnie]

hope this helps

[Motv18]

Computer ground dirty. Or trim valves buggered.

Single rams and with a stuck hi/low draw a butt tone of amps if stuck on high. Kills the feed of power to injectors and ignition.

Why the pp and jack do? Got me probably have a short.

Rpm is tps related probably and probably also related to the ground. Ie no voltage.

buddy suggestion: is to stack the terminals on what gets power first. The idea behind it being a series circuit is made based on how their stacked. Any large amp draw would starve power to what’s connected after it. And to look for shorts between alternator and battery. Since the run on the alternator once started.

[flabum1017]

Had a similar problem on a 225 Opti, whoever rigged it put the ground cable on the bolt that held the airbox on because the cabe was too short :rolleyes:, moved the ground cable to the correct place on the motor and all was good. I'd check all the connections on the motor.

I have also seen (in my 30 years as a marine mechanic) where they will rig the boat to draw power for all the accessories (stereo, lights etc..) off the engine harnes... big no-no.....

[mikej]

hope this helps

Do you have one for a 2010 250XS?