2006-2008 Polaris Snowmobiles FS/FST Service Manual., Page 53Get this manual
Maintenance ENGINE MAINTENANCE
FST Air Filter
FST models feature an air filter element to protect the turbocharger compressorReplace the air filter if damaged, dirty or saturated with engine oil
Valve Lash Adjustment
1234567Open the hood and remove the left-side door panelRemove the key from the ignition switchRemove the airboxclutch guard from the engine compartmentRemove the console assemblyRemove the seat assembly to gain access to the fuel tankRemove the fasteners securing the fuel tank to the tunnelCover the supply and return fuel hose connectors with clean shop ragDisconnect the fuel hoses from the fuel pump flangeDisconnect the fuel pump wiring harnessRemove the fuel tank from the snowmobileRemove the wiring harness connectors from the ignition coils and cam phase sensorVerify each connector is labeled with its positionLabel connector for re-assembly if requiredRemove the air intake tube (FST models) that is routed over the top of the valve coverRemove the ignition coils, then remove the valve coverRotate the drive clutch in the direction of forward vehicle operation until the rocker arms on the PTO-side of the engine are at TDC-compression strokeThe TDCcompression stroke can be identified when the rockers arms are loose and not contacting the camshaft lobesInsert feeler gauge between the valve shim and rocker arm tappet at each valve locationWrite-down each measurementCompare each measurement to the specificationIf the valve shim clearance is within specification, no change is requiredIf the clearance is outside the specification, the valve shim must be replaced with one that will satisfy the specification