I am still mystified as to how it happened, but the Morse gear/throttle selector became reversed during the journey from St Croix to Port Aransas. So pushing forwards selected reverse. Possibly it was like that when I departed St Croix Christmas Eve 2015: I know it was reversed when I rewired & restarted the engine off Port Aransas.
[From just past Grand Cayman, until just off Port A, I had no engine. There was a hidden break in the positive terminal lead from battery to starter motor, which I eventually, and accidentally, bypassed. The electrician in Camarinãs had mis-wired the setup, and I quite by chance bypassed the problem, only to top up with contaminated fuel].
Last week, I removed the Morse Controler and reversed the gear selector wire. There is insufficient room to reverse the gear selector cable at the gearbox. There is no room between the fuel tank and cockpit wall, and the tank is full, so rather than faff around I pulled the controller through the cockpit wall, mounting it flush with the wall. Before, it was mounted to the rear of the wall.
Accordingly, the controller is now about half an inch proud of the cockpit wall, but will be easier to access when I need to service the cables in future. I put a wooden shim between the Morse plastic cover plate and the cockpit wall. I will replace it with something prettier in due course. Meanwhile, I now go forwards when I select forwards.
Next I changed the impeller. Yanmar have fiendishly designed the 3JH2E such that this is a hard job, as the starter motor and raw water pump are in close proximity. Three hours later, the new impeller is in place. The old one was in good condition until I used long-nosed pliers to extract it. Here is an old raw water pump, with impeller in situ, and the extracted impeller:
The US Coastguard has finally issued my docs. I now need to change the marked port of registry on the stern from Douglas IoM to Corpus Christi, TX, and make an Official Number plate to be mounted somewhere in the boat.