2001 Mercury Mariner 50-60HP Factory Service Manual, Page 518Get this manual
BIGFOOT GEAR HOUSING
Loctite "271" (92-809819)
a -Fasteners and Washers (2 Each Side) -Locknut and Washer Bolt or Nut Torque 40 lb-ft (54 Nm) 16Check shift operation as follows: Place shift lever in forward gearGear housing should ratchet when propeller shaft is turned clockwiseResistance should be felt when propeller shaft is turned counterclockwisePlace shift lever in neutralPropeller shaft should rotate freely in either directionWhile rotating propeller shaft, place shift lever in reverse gearResistance should be felt when propeller shaft is rotated in either direction
IMPORTANT: If shift operation is not as described, preceding, the gear housing must be removed and the cause corrected