Parsimony still suggests the shift cable adjustment. I would particularly suspect that from it happening docking
, because human beings tend to shift in that situation while the engine
RPMs are still high.
Suggestion: First, make sure that all the attachments to the cable are tight, because slip rather than adjustment could be the problem. Then, disconnect the cable at the engine
, shift into forward, N, reverse and note the position of the arm in each case. Reattach the cable, and have someone shift at the helm
whille you watch. Did the arm go firmly to the three positions, or is it marginal between N and reverse?
There are lots of other nasty possiblities, but do remove that simple one from consideration before you hemorrhage time, money
, and greasy hands.