Flagship maize munchers upgraded

John Deere’s latest wide-body 9000-series forage harvesters offer a beefed up design over their 8000-series predecessors, with additional features, more power and bags more torque for higher outputs. David Williams

John Deere’s latest wide-body 9000-series forage harvesters offer a beefed up design over their 8000-series predecessors, with additional features, more power and bags more torque for higher outputs. David Williams tried them out.

Four new models, the 9600, 9700, 9800 and 9900, replace 8600, 8700 and 8800 versions. Externally new styling is the most noticeable indicator but the purr of low-revving V-12 power units replacing previous straight-6 engines on three models is also significant.

The new models are 625–970hp, gaining 127hp over the previous most powerful 8800, and John Deere claims up to 10 per cent extra productivity over models replaced, combined with 10 per cent fuel savings.
On the three largest models, Liebherr 24.2-litre V12 power units produce maximum power at under 1,400rpm and a John Deere PSS 13.5-litre 6-cyl engine is used in the 9600.
To make the most of the low-revving engines a new transmission was developed allowing all major components to operate at optimum speeds.

Engines are mounted longitudinally for optimum cooling efficiency and all can meet latest Stage 5 emissions regulations. “We couldn’t meet Tier 5 using the Cummins engines fitted to 8,000-series models and the Liebherr V12 has bags of power, a very flat power curve and maximum torque at just 1,350rpm,” explained John Deere harvester specialist Ross Skimming. “Previously maximum torque was between 1,700 and 1,800rpm and if the revs dropped below 1,700 then there wasn’t as much torque in reserve.”

To cope with the extra power the processing system has been strengthened. Crop is fed through an 850mm channel and a stronger shearbar, sharpening system and drum is incorporated.
ProDrive fully automatic transmission achieves 13mph in field mode at 1,200rpm and 40kph for transport at 1,400rpm, providing fuel savings.

Demanding field test

Farmers Guide tried the new 870hp 9800 in a dense crop of rye grown for a Worcestershire AD plant. The huge torque reserves made it easy to operate in variable crop and noise levels were low in and out of the cab. “Because the new engines are so low-revving, there is no need to reduce engine speed at each headland turn and full power is always available,” Ross explained.

Updates to the Active Fill Control trailer filling system include the ability to automatically fill trailers at the rear now, as well as at the side. New twin cameras supply loading information to direct the spout and the update will allow harvester operators to keep their eyes on the header rather than having to watch the trailer during opening up. The demonstration field posed quite a challenge for the system as extremely dry conditions and strong gusting side winds caused the crop to be blown sideways necessitating constant spout adjustment, but it compensated well and the dust didn’t seem to confuse the cameras.

Harvest management

The cab is similar to before but the demonstration machine was fitted with the latest HarvestLab 3000 NIR (near infrared) sensor. This provides real-time measurement and recording of crop yield, moisture and constituents including protein, starch and fibre either as totals or on field maps.

The latest HarvestLab system also enables AutoLOC (automatic length of cut) settings to be monitored, and adjusts silage additive dosing on the move, based on dry matter content.
A brand new display was fitted to the demonstrator. The 4640 10in screen is similar to the 4600 version supplied in latest 8000-series tractors but the 4640 also operates as a standalone unit, enabling swapping between machines. It’s larger than the current flagship 2630 version, with additional features for greater flexibility including the ability to continuously trickle-feed information rather than waiting for a summary of areas completed. A brand new app; MyOperations, allows constant remote monitoring of machine settings and task progress, from anywhere with a data connection.

The 2630 is the minimum specification to run HarvestLab and Ross suggested that although the demonstration machine had the new screen and current 2630 fitted, users are more likely to have a standard smaller screen for machine operation with the 4640 for HarvestLab.

Superior chop quality

“Consistency of chop is excellent,” suggested Ross. “Chopping the rye to 6mm for the AD plant, every sample we checked was almost spot on. The previous 8000-series harvesters were already praised by users for their chop performance but the new models are even better.”

For those harvesting maize John Deere has added to its range of kernel processors. The new XStream KP was developed in cooperation with US-based Scherer and has a large 250mm diameter and 50 per cent roll speed differential increasing processing intensity by 10 per cent at all chop lengths.

Also available are the standard Premium KP unit with a sawtooth teeth design and the XStream KP which can have the sawtooth profile or a new XCut design with a spiral groove across the roll surface. The XStream KP also has built-in temperature monitoring, keeping the operator informed of temperatures in work to help prevent overloading and downtime through bearing failure.