1985 OMC 65, 100 and 155 HP Models Commercial Service Manual, PN 507450-D, Page 301Get this manual
Screw in vacuum testerPump out to 76127 mm (3" 5") of mercury and see if vacuum holdsThen pump out to 381 mm (15") of mercury and checkIf the gearcase fails to hold on either test, put oil around suspected sealIf leak then stops or oil is drawn in, that seal is defectiveWhen the gearcase checks out OK, refill with the proper lubricant 1791
20Fill the gearcase with lubricant as followsThe gearcase must be in an upright positionCOA3165
Remove the oil level and the oil filldrain plugsReplace the seals if damaged Fill the gearcase with OMC Hi-Vis Gearcase Lube until lubricant appears at the oil level holeInsert the oil level plug firstInvert the gearcase and remove the oil fill hoseInstall the filldrain plugTighten the oil level and fill drain plugs to torque ofNm (6084 inIbsInspect the gearcase oil level after an engine test has been performed
21Apply OMC Gasket Sealing Compound to both sides of new water pump plate gasket and then install it and the impeller plate over the driveshaftAlso position the impeller drive pin as shownUse OMC Needle Bearing Grease to hold drive pin in positionThe drive groove in the impeller insert does not extend through both sidesThe open end of the drive groove must face the gearcase when assembled Lightly oil the impeller blades and slide it down over the driveshaft and engage the drive pin22Slide the impeller housing down the driveshaft until it is resting on the impeller23Press the water pump housing against the impeller as you rotate the driveshaft clockwise and the impeller will engage the housingInstall and tighten the four housing screws to torque ofNm (6084 inIbs24Adjust the shift rod as follows: Check from the shift rod hole to the surface of the gearcase using OMC Special Tool PIN 389997 (Universal Shift Rod Height Gauge), with the shift rod in "Neutral" and offset facing forward, rotate the shift rod full turns up or down as necessary for correct adjustment 100 Models560,32