Bleeding air from power tilt trim system

[Skimmercraft]

1985 mercury 115hp. The unit and reservoir is inside boat. Was low on fluid I've topped it up seems to still slowly drop after lifting and lowering 6-10 times. Can hear air in the system. Going to let it sit for while so air rises to top and remove filler to release air. There must be a bleeder somewhere tho? Can see a screw type thing on the left with alloy little turn screw would this be to release pressure or the bleed valve?

 

[Skimmercraft]

No Title

 

[Chris1956]

The pump/reservoir is self bleeding, but the trim cylinders are not. You need to bleed the trim cyinders individually, and they must be removed to bleed the "up" circuit.

Fill the pump, remove one of the bleed screws on the top of the trim cylinders. Run pump in the down direction. A spurt of fluid will exit the bleed port. Repeat with other trim cylinder.

Remove both trim cylinders from their mounts. Find the bleed screw, next to the spot where the hydraulic lines connect. Face the bleed port up, and remove bleed screw. Run pump in the up direction and see spurt of oil. Repeat with other cylinder.

Refill pump.