Polaris 2001 High-Performance Snowmobile Service Manual (PN 9916690), Page 111Get this manual
ENGINE Crankshaft Indexing (Continued)
6Bend the pointer or move the degree wheel until the pointer aligns with the 180 or 120 mark on the degree wheel7With the pointer aligned, make sure the degree wheel and pointer are secured and will not move out of positionRe-check accuracy of this location by repeating steps 4and 5The pointer should align with the 180 or 120 mark when the dial indicator reads .100 (2.54mm) ATDCIMPORTANT: Do not move the degree wheel or pointer after the initial setting on the mag end cylindersimply read the wheel and dial indicator8Remove the dial indicator and install in cylinder #2 or center cylinderRepeat steps 4and 5Note the degree wheel indication when the dial indicator reads .100 ATDCIt should be 180 or 1202) from cylinder #1Repeat procedure on PTO cylinder (#3) where applicableCylinder #3 should also be 120 2) from cylinder #1Symptoms of an out of index crankshaft can include: Difficulty calibrating carburetor (repetitive plug fouling on one cylinder with no other cause); Unexplained piston failure on one cylinder (i.esevere detonation, broken ring lands, piston holing); Excessive vibration of engine, backfiring, etc Rough idle, poor top speed