2001 Polaris Sportsman 400-500 DUSE and H.O. Service Manual, Page 129Get this manual
CRANKSHAFTCOUNTER BALANCEOIL PUMP INSTALLATION
Lubricate all bearings with clean engine oil before assemblyUse the crankshaft installation tool kit PN 2871283 to prevent damage to the crankshaft and main bearings during installation1Install the crankshaft into the PTO side crankcaseScrew the threaded rod into the crankshaft until the threads are engaged minimum of one inch (25.4mm)2Install the collar, washer, and nut onto the threaded rodHold the crankshaft and tighten the nut to draw the crankshaft into the main bearings until fully seatedLoosen the nut and remove the threaded rod from the crankshaftIf removal is difficult, install two nuts on the end of the threaded rod and tighten against each other3Install the proper shim on the magneto end of the crankshaft4Place the balancer shaft in the PTO crankcase aligning the timing marks on the crankshaft and balancer gearsInstall the proper shim washer on the shaft5Inspect the oil pump sealing surface on the crankcaseApply light film of engine oil to the surface and install the oil pumpNOTE: Do not use gasket sealer on the pump mating surfacesNOTE: After engine is assembled and machine is readied for field operation, oil pump MUST be primedFollow oil pump priming procedure on page 3.13