extra sacrificial zinc for saildrive
I use a galvanic isolator and have an extra zinc "fish" that is coupled to the the common ground on ye boate. no corrosion issues there.
i have yanmar ym30 with SD20 saildrive and flex-o-fold prop.
the saildrive appears to be electrically isolated from the common ground (which i assume is good to keep the aluminum leg from acting as a giant sacrificial anode for the rest of the boat).
i dont like how quickly the saildrive zinc corrodes, so i change it every 6-9 months.
does anyone think adding a second zinc "fish" coupled to the saildrive bolts from inside the hull and hung over the side would appreciably help anything/reduce rate of zinc usage? - i assume those bolts are electrically connected to the leg.