2008 Polaris Sportsman 500 EFI/X2/Touring/500 H.O. Service Manual, Page 35Get this manual
MAINTENANCE Fuel Filter
The fuel filter should be replaced in accordance with the Periodic Maintenance ChartEFI Example
Compression Test
NOTE: 500 4-Stroke engines are equipped with an automatic decompressorCompression readings will vary in proportion to cranking speed during the testAverage compression (measured) is about 60-90 psi during compression testSmooth idle generally indicates good compressionLow engine compression is rarely factor in running condition problems above idle speedAbnormally high compression can be caused by decompressor malfunction, or worn or damaged exhaust cam lobesInspect camshaft and automatic decompression mechanism if compression is abnormally highA cylinder leakage test is the best indication of engine condition on models with automatic decompressionFollow manufacturer's instructions to perform cylinder leakage test(Never use high pressure leakage testers as crankshaft seals may dislodge and leak)