1996 Mercury Force 25 HP Service Manual 90-830894 895, Page 65Get this manual
Care must be taken not to scratch the side surfaces of ring grooveScratching this area will damage the ring groove1 Pistons must be installed very carefully into cylindersPiston rings can be inspected thru exhaust ports6Top of cylinder bore has taper which permits the insertion of the piston into block using piston ring compressorPlace piston careflly into cylinder
Install piston ring in appropriate groove on piston using Piston Ring Expander ToolSpread rings just enough to slip over piston
2Check piston rings to be sure they fit freely in grooveLubricate rings and cylinder wall with 2-cycle oil
Crankshaft InstallationIf upper bearing (c) was removed from crankshaft" position bearing on crankshaft and using an arbor press install bearing making certain bearing is pressed all the way against step on crankshaft