2003 Polaris Deep Snow Snowmobiles Service Manual, Page 113Get this manual
ENGINES Crankshaft Indexing
Polaris crankshafts are pressed together or indexed" so the connecting rod journal center lines are 180 (twins) or 120 (triples) apart from each otherIt is sometimes necessary to check multi-cylinder crankshafts to verify that one cylinder has not been forced out of position relative to the other cylinder or cylindersCauses for out-of-index crankshafts include but are not not limited to: Hydrolock from water or fuel; Impact to drive clutch from foreign object or accident; Abrupt piston or other mechanical failure; Engine lock-up due to drive belt failure;
Following is method of checking: CAUTION: Disconnect battery ground cable and all spark plug high tension leads; ground high tension leads to engineDisconnect lanyard from engine stop switch before proceeding with the following steps1Securely fasten degree wheel on the flywheel or PTO end of crankshaftUse large degree wheel for more accuracy, and make sure it is mounted concentrically with the crankshaft center line2Sharpen coat hanger or section of welding rod and anchor it to convenient spotPoint the sharpened end at the outer perimeter of the degree wheel3Install dial indicator into the magneto end cylinder spark plug hole (front) (#1)(The ignition timing is referenced by the magneto end 4Rotate the engine to bring the piston to top dead center (TDC) on the cylinder with the indicator installed5Locate TDC as accurately as possible by finding the center of the point where there is no piston movementZero" the dial indicator at this pointContinue to rotate the crankshaft in the normal direction of rotation until the dial indicator reads .100 (2.54mm) after top dead center (ATDC)IMPORTANT: Do not allow the crankshaft to move from this position