Mercury Mariner V-250 V-275 Outboard Service Shop Manual 1990, Page 156Get this manual
80.1 nstalilift eye (91-90455) in flywheel at least turns Use suitable hoist to lift powerhead and install on driveshaft housingVerify mating surfaces of powerhead and driveshaft housing are clean and smoothUse new gasketNOTE: It may be necessary to rotate flywheel slig ht ly to align crankshaft splines with driveshaft splinesWhen lowering powerhead onto driveshaft housing, ve rify shift shaft is aligned with access hole in powerhead 82Secure powerhead to driveshaft housing with 610ck washers and hex nuts (a) and hex bolt (b) Torque hex nuts and bolt to 30 lbft(40.7 Nm) NOTE: If power head nuts are not torqued in sequence shown, you may get mi nor water leakage between powerhead and driveshaft housingFRONT OF ENGINE