Re: mercury 7.5 tilt?
If engine will not raise up easily when you lift up on the lower part of the engine, then your tilt tube may be dry. Those engines are pretty simple. I've owned a few and don't recall seeing anything other than the flat tilt support. Might want to take one of the grease fittings out of the tube first and see if it is rusty in there. if so, soak inside there with WD40 and try and work the motor up and down a bit. If it's just a little dry in there, pump some grease into both fittings with a grease gun until it comes out of the ends to see if that helps loosen things up a bit. Wish I could be of more help.
Happiness is a fine Mauser build.