Ayuh,..... I agree with BD on the cause,.....
I'd just use rags to do the clean up, 'n the gimble bearing, Could be greaseable, or sealed,.... donno which, both have been around for awhile,.....
Ayuh,...... Sounds like the outer cable sheath has a grove worn in it, allowing the inner(working cable) to move, before it can push/ pull the tiller arm,...
Nope, there should be 2, 7/16th nuts at the bottom of the transom that hold the manifold in-place, removing 'em allows pulling the manifold down, to unscrew the inside lines,....
