This is what I do for my small Evinrudes & Eltos.
Check your hardware or home improvement stores for
a grommet like these that fits on the water pipe.
Either type will do.
Then put it on a drill bit, where it fits tight, above the twist.
Spin it and using sand paper, or a flat file, take down one side till it fits.
Tubs.
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.