the motor is only made to go SO high, when cruising. you may need to top off your fluid. raise the motor all the way, lock it in place, top off the fluid. lower and repeat.
Your fluid level is probably low. Using TD's method, you can refill it and purge the air out. If it won't go up, have someone hit the "Up" switch while you lift up on the motor. Or you can use the manual release valve on the right side of the t/t to raise it. Turn the screw out a few turns (flathead screwdriver) then you should be able to raise the motor manually.
