02 Yamaha F 100 stuck in down position

[DPJII 123]

Replaced trim motor last year. Had boat out last about 2-3 wks ago and worked fine. Stored motor in down position since and now will not trim up. Disconnected wires from solenoid and straight wired to battery. Wires sparked could not hear motor running. Turned manual release screw and still can't manually raise motor. It will not budge. What would cause motor to be stuck down? Don't want to have to take entire motor off boat if I don't have to.

[boats.net]

Turn manual release out all the way against stop and unless something has it binding it should raise.