4. Grain pan
If unthreshed ear tips are appearing at the front of the grain pan, speed up the drum and then close up the concave. If problems persist, then consider fitting some form of enhanced threshing device. (See Extras box)
Speed up the drum and only once maximum rpm is reached start to tighten the concave.
If unthreshed tips persist on the grain pan, shut down the bottom sieve to channel them back through the returns system for re-threshing.
On certain New Holland combines returns cleaning is improved by a toothed rotor and housing at the base of the returns elevator. Set too tight, these can cause cracked grains. Adjust clearance accordingly.
Top tips to boost combine harvester output