2001 Mercury Mariner 50-60HP Factory Service Manual, Page 267Get this manual
CYLINDER BLOCKCRANKCASE
Checking Connecting Rod Bearing Clearance
IMPORTANT: Do not interchange used connecting rod bearingsReinstall bearings in their original position1Clean all the oil from the connecting rod bearing surfaces and connecting rod journals on the crankshaft
NOTE: Refer to instructions in Cylinder Block Reassembly for selecting and installing connecting rod bearings2Place piece of plastigauge on the connecting rod journalsaPlastigauge