50HP Yamaha power tilt trim 2 stroke

[Osprey165]

I hit a rock going about 5mph. The boat and motor just dragged over rock. The skeg is scraped up and it lifted boat slightly (161 Angler Smokercraft). I tried to lift motor with tilt to see damage and motor only goes up to I think the limit while running.
I got home bleed some air out of unit. Put motor up on safety tabs, disconnected lower mounting bolt/shaft, ran unit up and but it does not go into 'high speed gear'. Rechecked level after running up and down about 6 x. Remounted lower end of trim unit.
It will not lift motor above that point before it's breaking out of water...that high speed up point.
Any ideas or help appreciated. Motor only has 225 hrs on it. It's a 50TLR 6H5K L 1010857 K
P.S. I have had the skeg replaced/rebuilt 2x hitting rocks so the motor gas had some shock. This is first trim unit issue.

 

[ClassicAQ]

Refer to your service manual about checking the hydro pressure. System could be over pressurized, thus preventing full tilt.

 

[Osprey165]

I did bleed some air pressure off the unit which pushed some fluid out. I them manually lifted motor onto the safety/trailering tab. Next I removed the lower mounting shaft of the unit and fully extended and retracted many times. I rechecked fluid level which was ok. Remounted lower shaft. It still does not lift motor into the 'out of water position'

 

[Osprey165]

I'm looking for a NEW tilt trim unit for this motor now.

 

[Osprey165]

Ok so the marina shared a trick with me.
They said to open the manual letoff screw on unit and lift motor fully and let go to bottom of travel removing max down bar. Lift motor and drop 6 or more times. After 15x I tightened manual screw. It the switch and wa-la it's now functions fine. After finding out those trim units cost $1200+ I'm buying the the whole shop pizza lunch.

 

[99yam40]

good to hear it is going again.
I guess it was some valve the was hanging up, but do not understand how doing what you did would free it back up

 

[ClassicAQ]

Ok so the marina shared a trick with me.
They said to open the manual letoff screw on unit and lift motor fully and let go to bottom of travel removing max down bar. Lift motor and drop 6 or more times. After 15x I tightened manual screw. It the switch and wa-la it's now functions fine. After finding out those trim units cost $1200+ I'm buying the the whole shop pizza lunch.

Could you detail this procedure again please. You lose me with your words in bold above. Thanks.