2007-2008 Polaris IQ Snowmobiles Service Manual, Page 124Get this manual
Engine and Cooling Systems ENGINE INSPECTIONS
Cylinder Head Inspection
Using flat bar and feeler gauge, inspect each cylinder head for warpingReplace head if warping exceeds .003" (.08mm)= In mmTaper Limit.002" (.051mm) Out-of-Round Limit.002" (.051mm)
= In mmCylinder Head Warp Limit .006" (.015mm)
Cylinder Measurement
Inspect each cylinder for wear, scratches, or damageIf no damage is evident, measure the cylinder for taper and out of round with telescoping gauge or dial bore gaugeMeasure the bore 12" from the top of the cylinder; in line with the piston pin and 90 to the pin to determine if the bore is out of roundRepeat the measurements at the middle and bottom of the cylinderUse the chart below and record all measurements