2004 John Deer Buck Utility ATV 500, 500EX and 500EXT Service Manual, Page 93Get this manual
"Specifications" section for capacityStart engine and let idle for few minutesEnsure oil filter area and drain plug areas are not leakingStop engineWait while to allow oil to flow down to crankcase then check oil levelRefill as necessaryDispose of oil as per your local environmental regulationsThe pressure should be between 101 kPa (14.7 PSI) and 500 kPa (72.5 PSI) Remove the plug screw no7, sealing ring no8, compression spring no9 and piston no10
Inspect piston for scoring or other damagesEnsure vehicle is on level surfaceRemove: skid plate under vehicle engine oil screws no1 retaining oil strainer cover no2 oil collector no3 and O-ring no4 oil strainer no5For installation, reverse the removal procedurePay attention to the following detailsAlways install new sealing ring when the oil pressure regulator is removedWhen the repair is donePerform an oil pressure test then test drive to confirm all is working wellCompression Spring Free Length New Nominal Service Limit 43.5 mm (1.71 in 42 mm (1.65 in Check compression spring for free length, squareness or other damage