2000 Yamaha YFM400FWA(M) Factory Service workshop Manual, Page 191Get this manual
CRANKSHAFT AND OIL PUMP
CRANKSHAFT AND BALANCER INSTALLATION 1.Install: Crankshaft Crankshaft installer set 1: PNYU-90050 Buffer boss installer set 2: PN90890-04088 Adapter #11 3: PNYM-33279 Crank pot spacer 4: PNYM-90070-A, 90890-04060 NOTE: Hold the connecting rod at the Top Dead Center (T.D.C with one hand while turning the nut of the installing tool with the otherOperate the installing tool until the crankshaft bottoms against the bearing