Suzuki outboard motors 1988 2003 repair manual., Page 270Get this manual
8-2 LOWER UNIT The main physical differences lie in the shifting mechanism (mirror image) and the propeller shaftThe counterrotating unit has shoulder machined into it for the forward bevel gear tapered roller bearingAnother difference regards nomenclature: what would be the forward gear on standard unit becomes the reverse gear on counterrotating unit and what would normally be the reverse gear on standard unit, becomes the forward gear on counterrotating unitThe pinion gear remains the same and driveshaft rotation remains the same as on standard lower unitMirror image shifting mechanisms produce counter rotation of the propeller shaftThis type lower unit consists of the same major identical components as the standard unitOn standard lower unit, the cam on the shift shaft is located on the starboard side of the shifterTherefore, when the rod is rotated counterclockwise, the clutch shifter is pulled forward and the forward gear is engagedOn counterrotating lower unit, the cam on the shift rod is located on therside of the shifterTherefore, when the rod is rotated counterclockwiset the clutch shifter is pushed back and the gear in the aft end of the housing (which normally is the reverse gear) is engagedIn this manner, the rotation of the propeller shaft is reversedThe same logic applies to the selection of reverse gear Counter-rotational shirting is accomplished without modification to the shift cable at the shift boxThe normal setup is essential for correct shiftingThe only special equipment the counterrotating unit requires is the installation of left-hand propellerThe lower unit consists of the driveshaft, water pump, pinion gear, bearings, forward and reverse gears, propeller shaftThe shifting mechanism and the lower unit housingThe housing is bolted to the exhaust housing, which places the driveshaft and water tube(s) through the center of the exhaust housingThe water tube carries water from the water pump to the powerheadThe driveshaft splines insert into the crankshaft which then transmits power from the powerhead to the gearcaseA pinion gear on the driveshaft takes the power from the driveshaft and transfers the power to the propeller shaftThe powerhead driveshaft rotates in clockwise direction continuously while the engine is running, propeller shaft direction is controlled by the gearcase shifting assemblyThe lower unit can be removed from the engine without removing the engine from it's mounting on the boatThe lower units in this chapter differ somewhat in their design and construction and require different servicing proceduresThe lower unit is normally trouble free until water enters the gearcase, the operator shifts incorrectly, or the oil is not changed regularly and corrosion enters the unitConstant maintenance is required to prevent these problemsBecause the unit is normally underwater, extra care must be taken to prevent problemsShifting the unit in and out of gear needs to be quick and positive to prevent rounding over the shift clutch dogsSlow engagement will damage the partsThis problem is evident when the unit jumps out of gearFollowing the recommended oil change schedule allows the oil to be drained and checked for contamination, especially water intrusionA milky looking oil is sign of water has entered the gearcase and it must then be pressure tested to check the seals and the leaks repaired to prevent damage to the bearings and gearsSTANDARD ROTATING UNIT
Non-Reverse Type
Some of the smaller engines equipped with neutral, but no reverse-gear, utilize spring-loaded clutch to shaft between neutral and forward gear Reverse Type
On Suzuki outboard engines equipped with reverse gear, sliding-type clutch engages the chosen gear in the gearcase housingThis clutch when engaged, creates direct connection that then moves the power flow from the pinion to the propeller shaftPower flow in the lower unit goes through the driveshaft into the pinion gear, which constantly turns the forward and reverse gears in opposite directionsThe clutch dog is part of the shaft mechanism and IS splined to the propeller shaftThe clutch dog is held in the central position (neutral) between the forward and reverse gearsWhen the shift shaft (rod) is moved, the shift cam (shifter) moves the follower (shifter shaft), which in turn, moves the clutch dog into mesh with the selected gearPower is then transmitted from the gear through the clutch dog into the propeller shaft, and finally to the propeller V4 and V6 Smooth-Shift