JUST BOUGHT A JINMA 404 WITH A HUNDRED HOURS ON THE CLOCK . DON.T KNOW IF THE FACTORY FLUIDS WERE EVER DUMPED , HAVE HEARD THEY SHOULD BE . ANY OPINIONS ON THE SUBJECT ?
With 400 hours, all the fluids should be changed, regardless of whether they're factory or after-market. Cheap protection. Also, adjust clutch, tighten all bolts, adjust valve lash and re-torque the head gasket.
Drain bolt on the bottom of most of them, if not you may have to suck it out with a squeeze bulb. Fill to the dipstick mark with engine oil. You fill it either through the dipstick or the mushroom-shaped cap on the top. If the drain bolt is on one side/end there may be a bolt directly above it that is the witness hole - pull that bolt and fill with new fluid until it weeps out the upper bolt then button things up.