1/ did he mean use a hammer on the nut , or on the end of a wrench attached to the nut , like a breaker bar ? 2/ i once saw a morse gearshift cable which fried itself on the engine exhaust because the engine installer didn't use enough harbor freight zip ties to actually keep the too-long morse cable looped high enough off the exhaust manifold. the exhaust heat and excess cable sag allowed the morse to fry itself. which froze the cable (with gearshift in forward, of course) which then disconnected the end of the morse from the teensy little press pin that yanmar used to hold the morse onto the gearshift lever. the worst part was hitting the dock in full forward , thinking the gearshift was in reverse, when in fact unbeknownst to me the fried morse had it stuck in forward. the admiral kept yellling REVERSE REVERSE but the boat wasn't slowing as it usually did as i approached the slip ( with a 15 kt stern wind of course.) (and in front of the whole dockside 5pm drinking crowd.) so i of course throttled it up, not realizing that for lack of a zip tie or 5 from harbor freight, i was about to hit the dock at 5 knots. in forward. the best part was waiting 3 weeks for a new morse cable OF THE CORRECT LENGTH . and also having an unhappy person standing below next to the engine to shift gears by carefully pulling on a line thru the hole in the end of the gear shift lever.