06 F50 engine dies when trim activated

[jack9977]

Last week while going upriver, on step at about 80% throttle - the trim acted like it was stuck then released. Trimmed again same action - like it hung up. Next time the engine died. The starter motor and trim would not activate at all. Was unable to restart for about 10 minutes, then engine would turn over and start and trim worked. This happened on two occasions.

Second time, we got into shallow water, trimmed up and engine died. Drifted about 10 minutes again and then starter and trim became operable again.

Battery seems strong and shows 12-13.5 volt on gauge. Ran motor and activated trim at low rpm and higher rpm for about 20-30 minutes (while anchored at beach) with no problems.

Other threads suggest testing battery, wiring, connections, etc. I plan to do this and if no luck will take to a shop.

Does anything obvious jump out at anyone?

[BaileysBoat]

Diagnostics begins at the battery. Voltage doesn't tell the whole story. Has to pass a load test, than clean all the connections.

Let us know what you find.

[THerbert]

Same thing happened to me a week ago. Was running in shallow water, went to trim up and lost everything at the motor. Found the ground cable where it bolts to the motor was loose.

[jack9977]

Continuing to check connections, battery

Thanks for the feedback. Battery checked ok at load (battery is one year old). One cell was low so will charge back up. There was up to 1 volt drop on positive cable so I'll clean and check all cable connections again.

Mechanic that checked battery suggested checking output of the alternator. I've not seen any diagnostic comments. Will probably take to shop for alternator diagnostic if engine/trim keep acting up.

[jack9977]

Problem solved!

I cleaned and retightened each terminal on the motor. There appeared to be some "light" corrosion on several negative terminals. Also cleaned the battery terminals which needed it. Took boat out on river for over an hour. Ran like a champ - on step charged at 14 volts - when trim activated - voltage dropped to 12 volts then recovered to near 14 v. Sweet!

Trimmed about every 2 mi or so for over an hour and not a wobble. I really appreciate this forum. Mr Rodbolt's advise is invaluable. Seems like lots of problems can be traced back to poor or corroded electrical connections.

Thanks to all who contribute!