Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-42794--1, Page 290Get this manual
Drilling Mounting HolesWithout Drill Fixture To position outboard mounting holes correctly, do the following: 1Lift outboard using suitable lifting equipment and procedure, see "Installing Outboard" following Place outboard on transom making sure to hold outboard at correct height and at centerline of boat as determined in steps and preceding2Mark mounting holes on transom using mounting holes in clamp brackets as templateRemove outboard or use long 716 in(11 .112mm) diadrill bit and drill thru clamp bracket to make mounting holesInstalling Outboard 1Use lift harness or 91-90455 (a) (91-644002A2) or lifting eye (b) (9175132 or 91-90455) threaded into flywheel minimum of turnsLift outboard on boat transom using hoist having minimum lifting capacity of 500 pounds (227kg) Apply marine sealer to shanks of mounting bolts (not threads) and secure outboard to transom with bolts, flat washers and locknuts, as shownBe sure that installation is water-tight
Three Ram Trim System
91-90455