hi i have a 60 mercury 4 stroke.i lower the outboard with the tilt. and goes down fine. and back up again.no problem. but when under way and try to tilt the engine it will go up a little way then starts stutter.if i increase the engine speed it lowers itself back to and will not tilt up under load.the motor runs fine.with no problems.regards gareth.
I had one with similar, When under load or Mobile hesitated and only moved sometimes. I added more Fluid to Pump ; bled it (removing air) and went o.k.
I filled with Leg Down... Hope this helps..