2004 SR Johnson 2-stroke 40, 50HP Service Manual, Page 192Get this manual
POWERHEAD CLEANING
CLEANING
IMPORTANT: Before inspecting or assembling
powerhead, all internal components must be completely clean and free of contaminantsRemove any carbon accumulation from exhaust port areasRemove any carbon accumulation from cylinder head combustion chambersIf cylinder walls are glazed from extended use, use rigid, medium grit cylinder hone to resurface wallsUse slow RPM for best oil retention and ring sealingWhen finished, cross hatch pattern of 22 to 32 should be visible in the cylinder wallThe pattern should be uniform in both directions
WARNING
To avoid personal injury, wear eye protection and rubber gloves when using Gel Seal and Gasket RemoverCarefully remove any carbon accumulation from the tops and ring grooves of the piston using Engine TunerA ring groove cleaning tool can be made by breaking an old ring and grinding an angle on its endDo not damage ring grooves while cleaningThoroughly wash entire cylinder block and crankcase with warmsoapy water to remove all traces of contaminantsAir dry cylinder block and crankcaseBlow all holes and passageways with compressed air