Cam Chain Help Needed Sportsman 500 - Polaris ATV Forum
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post #1 of 3 (permalink) Old 05-23-2019, 02:10 AM Thread Starter
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Cam Chain Help Needed Sportsman 500

I recently picked up a 1997 Sportsman 500 that had sat for an extended period of time. After cleaning the fuel system I turned it over and the starter spun really fast. When checking to make sure the engine was on TDC and if the valves were in spec I noticed that the cam Chain does not spin when you turn the crank shaft. There is tension on the cam Chain but it is not spinning with the crankshaft when you turn it over. I wasn't sure if it could have slipped off the crank sprocket or maybe I sheared a woodruff key. Not quite sure where to start and would rather not pull the flywheel if I don't have to. I appreciate any insight. Thanks!
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post #2 of 3 (permalink) Old 05-23-2019, 07:16 AM
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Sorry, but you are going to have to remove the flywheel, stator and the plate behind the stator to see whats going on even if it's just to put the chain back on the sprocket. The only time I have seen the key under the crankshaft sprocket shear was when a previous service tech left the spanner nut loose (or simply did not tighten it to spec) - the engine ran fro several years and then one day just stopped running. If you are lucky, it didn't bend any valves, but get the service manual, clear out plenty of room around it and get busy. Good news is it can be done without removing the engine.

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post #3 of 3 (permalink) Old 05-23-2019, 08:28 AM
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Maybe the chain is just off the sprocket?
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