Mercury Mariner Outboards 2.2 / 2.5 / 3.0 Service Shop Manual, Page 45Get this manual
Crankshaft Check (off-centering) of crankshaft using "vee" blocks and dial indicator as follows: aPosition crankshaft in "vee" blocks as shown bRotate crankshaftMovement of dial indicators must not exceed .001 in(.05mm) If over .001 in (.05mm)replace crankshaft assembly
Reed Valve
1Inspect reed petals for signs of fatiguecracks or chipsThe reed petals should fit flush or nearly fl ush against the seat2Check for wear (i ndentation on face of seat)If reeds have made indentations in the seat, the crankcase cover cylinder block will have to be replaced3Check reed stop opening as shown Replace reed stop if opening is not within specification
.236 in to .244 in(6 to 6.2mm)
Reed Stop Opening
Crankshaft Ball Bearings and Piston Needle Bearing
CRANKSHAFT BALL BEARINGS Grasp outer race of crankshaft ball bearing and work race back-and-forthThere should not be excessive playLubricate crankshaft ball bearings ith light oilRotate outer bearing race Bearing should have smooth action and no rust stainsIf bearing sounds orfeels "rough" or has "catches" replace bearing PISTON ROLLER BEARING Thoroughly inspect piston roller bearing If bearing is rusted, fractured, worn, galled or badly discolored, replace bearing