1970-1979 Ski-Doo Snowmobiles Service Manual, Page 63Get this manual
56 8Refer to Component Inspection and inspect cylinder, piston, pin, and ringsCylinder Head, Cylinder, Piston, and Ring Installation
CHAPTER FOUR
1Lubricate piston pin needle bearings with oil and insert bearings into connecting rod2Slide piston over connecting rodBe sure that mark or letters AUS face exhaust side of engine (Figure 17)3Using piston pin installation tool or appropriately sized wooden dowel, install piston pin through piston and rod endCAUTION
Exercise care when installing pin to avoid damage to connecting rod needle bearingIf wooden dowel is used to drive in piston pin, ensure that piston is properly supported so that lateral shock is not transmitted to lower connecting rod bearing, otherwise rod andor bearing damage may occur
4Secure piston pin to piston with circlipsWhen circlip is properly installed in groove, rotate circlip so gap in clip is not directly on notch break of piston (Figure 19)NOTE: Stuff clean rags around connecting rod in crankcase to help prevent circlip from dropping into crankcaseCAUTION