Remove the rubber sleeve from the neck of the die grinderRemove the 4 screws that hold the neck onset aside the plastic coupler & large washerWhile holding the neck in a vice, unscrew the collar nutSet aside the smaller washer & felt washer that were behind the collar nutUsing the handle of the crescent wrench, unscrew the butterfly nutSet aside the butterfly nutPlace new shaft in the neck.Place metal washer and felt washer into neck, then reinstall collar nut.Reinstall butterfly nut. Note the vice is holding the shaftReinsert plastic couplerPlace large washer in neckHow it looks before reattaching the neckReattach the neck with 4 screws, be careful to line up exhaust vents to the sideSlide the rubber cover back onto the neck
