2007-2011 Polaris IQ Snowmobiles Service Manual, Page 251Get this manual
Engine and Cooling Systems DisassemblyAssembly Process 1To remove the pistons, follow the process for removing the cylinder head and cylinders from the engine2To remove the crankshaft, follow the process for disassembling the crankcase assembly3With the piston out of the cylinder, remove one of the c-clips and discardNever re-use piston c-clips4Push the piston pin out of the piston and upper rod bearingsInspect the pin for galling and abnormal wearInspect the needle bearing by feel and replace as required5New pistons are supplied with new rings and piston pinIt is recommended that new needle bearings be installed as well6When installing new piston, insert one c-clip into the piston making sure the open end is 180 opposite of the groove opening7Apply liberal amount of Polaris two-stroke engine oil to the needle bearings, piston pin and piston assembly8Push the pin in to the piston, then through the needle bearingInstall the remaining c-clip with the open end is 180 opposite of the groove openingNOTE: Always use new cylinder base gaskets9Apply liberal amount of Polaris two-stroke oil to the cylinder wallAlign the piston ring gaps around the piston locating pinsCompress the upper ring, then carefully slide the cylinder down over the ring10Compress the lower ring, then slide the cylinder down over the ring