1987-1993 Mercury Mariner Outboards 70/75/80/90/100/115HP 3 and 4-cylinder Factory Service Manual, Page 160Get this manual
IMPORTANT: On some engines, BOTH the piston rod and rod cap bolt holes are threadedThe rod cap and rod must be aligned and held tight together when threading in boltCheck that mating surfaces are tight together after bolt enters the threads in the piston rod S Replace lower crankshaft End Cap1Coat mating surface with Perfect SealDO NOT coat O-ring seal2Bolt to block (2 bolts)finger tightenlightly
Connecting Rod Cap Alignment
1Check each connecting rod for correct alignment by carefully running fingernails up and down edge of rod capIf not aligned, ridge can be seen or felt at the separating lineCorrect any misalignmentFront View Correct Front View Incorrect
aMating SurfaceO-ring Seal
Crankcase Cover to Block
LOCTITE MASTER GASKET SEALANT,92-12564-1 is used; it comes as kit, which includes Primer and SealantInstructions contained in the kit MUST BE FOLLOWED EXACTLY(Clean both surfaces)IMPORTANT: Extend sealer to edge on each center main journal to prevent blow-by between cylinders