2001 Edition Yamaha F225A and LF225A Outboards Service Manual, Page 351Get this manual
Bracket unit Symptom: Power trim and tilt unit does not hold the outboard motor upCheck that the manual valve is closed
Is it closed? Yes Check the power trim and tilt fluid level
Close the valve
At specified level? Yes
Add fluid to the correct level
Disassemble the power trim and tilt unit, and then check the filters for debris or dirtStuck foreign substance or clogs? No Check the fluid passages for clogs or debris