'91 Mercury 40 HP power trim/tilt won't hold in up position

[lolpontooner]

The power trim won't hold in the up position. "Leaks" down, even though I see no evidence of leaking seal or fluid. Any suggestions?

 

[strombolichef]

You're going to have to buy a rebuild kit and a manual and then pull off the tilt trim assembly and rebuild the seals