1987-1993 Mercury Mariner Outboards 70/75/80/90/100/115HP 3 and 4-cylinder Factory Service Manual, Page 154Get this manual
IMPORTANT: There are two types of pistonrod assemblies available for the cylinder powerheads: Design Bottom guided (centered in bore by crankshaft) Design Top guided (centered in bore by piston) DESIGNBOTTOM GUIDED
Top guided piston and rod assembly can be installed in powerhead with bottom guided piston and rod assembliesHowever, individual components cannot be intermixed I.E Top guided piston cannot be used with bottom guided rodDESIGNTOP GUIDED