Bravo One trim issue
 

2004 350 Mercruiser with Bravo One

Trim works fine up and down, except it gets stuck when trimmed all the way up in trailer mode. I have to bleed pressure off fittings at pump to get it to go down. Once pressure is bled just a little and lines are tightened back up everything works fine. Again it will cycle fine at all levels until it reaches full up position and will stick again. No unusual noises, trim cylinder shafts look smooth, tried it without anodes on cylinders. Also tried standing on drive while trim was cycled to no avail. Any suggestions would be greatly appreciated. Thank you

I would guess its the trim/limit sender on the side of the gimbal going bad...

When My trim would go UP but not DOWN without force, I replaced the pump and valve assembly, and it fixed it.
I could force the trim down by putting it in gear (in water) and then holding the down.

https://www.marineengine.com/newpart...m=MER865380A25

I have 2001 350s, but check your engine serial number/drive number before buying any parts.

aftermarket ones are cheaper FYI.

this assumes when you trim down your pump is running. if it's not running, you have another issue.
you could test the trim limit sender by removing it / adjusting it and see if the condition changes. I think it's the one on the starboard side, but check your manual.