Monday, July 22, 2013

MODIFYING A GLEANER N7 TO IMPROVE HARVESTING WITH STRIPPER HEAD

7/28/15- Update: -- We installed new floors under the distribution augers.  We inadvertently cut the lip where material is released onto the accelerator rolls a quarter inch higher than what we added in 2013.  This was a problem.  The material would not release onto the accelerator rolls properly and would periodically jamb material between cage and auger.  The fix was quite easy.  Using a thin (0.045)cutoff wheel on a 4.5" grinder, we marked and cut 0.75" off the lip of the auger trough over the accelerator rolls.   All our issues appear to have gone away.  It looks great behind the combine.  Our grain sample, which was not as good as in the past, cleaned up, better than in the past, and our capacity is back, --or better.  While we were in the midst of replacing parts, (distribution auger drive belt, a broken rear feeder chain, and drive shaft for the rear feeder chain), we were told that feeder chains and drive shafts tend to have a shorter life when using a stripper head on the older Gleaners.  No reason given.  The chains are easy to check, but the shaft is not.  The center chain had every link holding a bar, cracked.  The side chains were fine.  The shaft broke under the center sprocket.  My current thinking is that when the chain is replaced, we also consider replacing the drive shaft.
9/20/13- Update: -- Adding the 1.5" to the cross auger (distributor) trough over the accelerator rolls appears to be slightly too high.  That small change was all it took to move the grain - maybe too far.  We may cut it down a 1/4" for next year, although for the most part we could live with it as is.  Although we have only used the standard header on mustard, it doesn't appear to have upset the "original" material handling capability.
      We rebuilt a spare cross auger (distributor) using an 8" pitch and made provision for bolting on flight extensions to extend either left or right.  Also, provision was made to put kicker bolts along the shaft to move material onto the accelerator rolls at various points.  This auger was not needed, so never used, and probably will never be used.
   
       Last year we did not have a clue what to expect from the combine.  As far as I know this is the oldest combine(1985) to be fitted with a new (2012) Shelbourne 32' stripper head.  We were very pleased with the results of the header on the three types of crops harvested -- winter wheat, spring barley, spring mustard.  What we weren't prepared for was the change experienced once the grain was in the combine.  Along with higher capacity, we also had higher loss.  Without straw in the machine the grain was not distributed across the sieve as before.   The grain, chaff, and a little stubble came up the feeder chain, dropped onto the rotor and concave; and then, instead of being carried along the distributor augers and and dropped more or less evenly across the face of the sieve, the material went straight through the concave onto the right side of the sieve, overloading that section.
       This will be a trial and error process that may take time to solve.  Our first idea is to add 1.5" to the height of the cross auger trough and change the auger from a 6" pitch to an 8" pitch to move material away for the concave area quicker.  At this time we do not have a way to adjust the trough height.  If this modification turns out to be bad, it will take about 3 hours to convert back to the original configuration.