1987-1993 Mercury Mariner Outboards 70/75/80/90/100/115HP 3 and 4-cylinder Factory Service Manual, Page 161Get this manual
REATTACH CRANKCASE COVER After the application of the Loctite Master Gasket Sealing Kit, place crankcase cover onto block, and alignS Recheck that bolt holes and bolts are clean to assure accurate torqueS Insert boltsnote sizes and finger tightenS Loctite End Cap Bolt and install in remaining (End Cap to Cover) holeS Torque Crankcase Cover BoltsIMPORTANT: This is Double Torque Pattern10 12
Cylinder Block Cover
S Align cover and gasket on block
aCoverGasket
S Install thermostat cover and components, as follows: 1Insert poppet valve (d) into valve seat (f)2Install cover gasket over poppet3Insert thermostat (h) into well4Align cover, with poppet spring (a) seated as shown5Depress cover, and insert boltsfinger tightenNote seating of thermostat gasket (h) and poppet gasket diaphragm (c)These, and gasket "g" are replaceable when necessary