Hard to say whats wrong - you need to go on a bug hunt.
You'll need to manually lift the engine to it's full tilt-up position. I've used a strap below the cavitation plate, hooked to a come-a-long, hooked to an overhead beam to do this. Turn out the manual unlock release screw on the left side of the engine, then slowly lift the engine. Then, turn down the lock lever to hold it up on the right side. Then open the hydraulic fluid reservoir and make sure you have fluid to the top, or near the top. If not, fill to the top, turn up the locking lever, close the manual release screw, and slowly release the come-a-long. The engine may or may not stay in place. If it does stay in place, then slowly unscrew the manual release and it will drop. If you replaced a lot of hydraulic fluid, you may need to do this procedure several times to get the air bubbles out of the hydraulic system. During this process see if any fluid is leaking from the seals around the trim rods, or the main tilt hydraulic plunger.
While you have the engine locked in the up position, test your tilt-trim motor to see if it will run and raise the trim plungers. If not, then follow the wire from the trim motor to its plug under the cowling and unplug it. Apply a 12V power source to the two pins - it doesn't matter which is is positive and which is negative since this is a full switching motor. If the motor does not run smoothly, it will need to be replaced. You can do that yourself. (BTW - the OEM replacement motor is very pricey - $450 +/-. There is an API equivalent (PT607 NM) for about $150.00, but you must reverse the wires - blue to green and green to blue.)
