Index Snowmobiles / ATV Snowmobile Polaris 440 PRO X Fan, 440 PRO X, 600 PRO X, 700 PRO X, 800 PRO X - service manual 2003 year
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ENGINE 2.52 Crankshaft Indexing Polaris crankshafts are pressed together or ‘‘indexed” so the connecting rod journal center lines are 180 q (twins) or 120 q (triples) apart from each other. It is sometimes necessary to check multi-cylinder crankshafts to verify that one cylinder has not been forced out S Hydrolock from water or fuel; S Impact to drive clutch from foreign object or accident; S Abrupt piston or other mechanical failure; S Engine lock-up due to drive belt failure; Following is a method of checking: CAUTION: Disconnect battery ground cable and all spark plug high tension leads; ground high tension leads to engine. Dis- 1. Securely fasten a degree wheel on the flywheel or 2. Sharpen a coat hanger or section of welding rod and 3. Install a dial indicator into the magneto end cylinder 4. Rotate the engine to bring the piston to top dead 5. Locate TDC as accurately as possible by finding the s (2.54mm) after top dead center (ATDC). Crankshaft Indexing (Continued) 6. Bend the pointer or move the degree wheel until the pointer aligns with the 180 q or 120q mark on the degree wheel. 7. With the pointer aligned, make sure the degree wheel and pointer are secured and will not move out of q or 120q mark when the dial indicator reads .100s (2.54mm) ATDC. IMPORTANT: Do not move the degree wheel or pointer after the initial setting on the mag end cylinder - simply read the wheel and dial indicator. 8. Remove the dial indicator and install in cylinder #2 or center cylinder. Repeat steps 4. and 5. Note the degree s ATDC. It should be 180q or 120q (r 2q) from cylinder #1. Repeat procedure on PTO cylinder (#3) where applicable. Cylinder #3 should also be 120 q¢r 2q) from cylinder #1. Symptoms of an out of index crankshaft can include: S Difficulty calibrating carburetor (repetitive plug fouling on one cylinder with no other cause); S Unexplained piston failure on one cylinder (i.e. severe detonation, broken ring lands, piston holing); S Excessive vibration of engine, backfiring, etc.; S Rough idle, poor top speed. Dial Indicator Degree .100 ATDC |