2006 Johnson SD 30 HP 4 Stroke Outboards Service Manual, PN 5006592, Page 206Get this manual
GEARCASE DISASSEMBLY
Assembly
Install new gasket and the plate on top of the gearcaseInsert the impeller key in the driveshaft, then slide the impeller onto the driveshaftMake sure that the key and keyway on the impeller are aligned
DISASSEMBLY
IMPORTANT: Clean and inspect all components during disassemblyReplace all damaged components, seals, O-rings, and gaskets upon assembly
Pre-Disassembly Inspection1
Before disassembling the gearcase, examine the followingGearcase housingAll gasket surfaces must be free of gasket materialAll threaded holes must be free of corrosion and sealerMake sure that the inside of the gearcase is clean and free of debris Gearcase anodeIf the anode has been reduced to two-thirds of its original size, it must be replaced DriveshaftCheck the splines for chips, wear, and cracksBearing and gear surfaces must not show signs of metal transfer, corrosion, or discolorationSevere spline wear might indicate exhaust housing or gearcase that has been distorted by impact damage Propeller ShaftCheck for bent or damaged shaftCheck for twisted splines and damaged threads Shift RodCheck for misadjusted, bent, or binding rodA misadjusted shift rod height can cause shift difficulty, loss of boat and outboard control, and gearcase damage Water intake screenThe screen must be clearIf the screen cannot be adequately cleaned, replace itDifferent screens are available and should not be mixedRefer to the correct parts manual for listing and description Water pumpCheck impeller for wear, crumblingand hub bondingCheck impeller cup and plate for scoring and distortion