Mercury Mariner V-250 V-275 Outboard Service Shop Manual 1990, Page 18Get this manual
4Place rear thrust hu on pro pell er shaftas shown5Place locki ng ab washer on propell er shaftthen hread propeller nu on shaft6Place propeller nut into recess in locki ng tab washer and torque propeller nut mi nimum 55 lbft(74.6 Nm), making certai that nut is recessed into locking tab washer7Bend tabs from lock ing tab washer down into grooves of propeller hub to secure propeller nut8After firs use, bend the labs st raight, retighten propeller nut [minimum of 55 lbfl(74.6 Nm) 1and again bend tabs down in propeller hub grooves (check per iodically for tightness) IMPORTANT: Some boatoutboard combinations, that do not use the trim adjustment bolt and are trimmed to the full "in" trim angle, will nol experience any undesirable and or unsafe steering conditions during planing speedThus, not using trim adjustment olt may desiredHowever, some boats with outboard trimmed to the fullin" trim angle at planing speeds will cause undeslreable and or unsafe steering conditionsIf these steering conditions are experienced under no circumstances should the outboard be operated without the trim adjustment bolt and without the bolt adjusted in the proper holes to prevent unsafe andling characteristics1T he tri ad justment bolt is installed when the outboard is shipped Water test the boat not using the ri adjustment boltIf undesirable andor unsafe steering cond itions are experienced (boat runs with nose down), install trim adjustment bolt in proper ho les to prevent unsafe handling characteristics