Pneumatic Down Force

1. CAUTION: Avoid serious injury from exploding parts due to overpressurization or operating the system without all components in place.

   • Do not inflate system above 827 kPa (8.2 bar) (120 psi).
   • Do not remove pressure relief valve.
   • Do not pressurize system unless all row unit components are in place.
   
   

   IMPORTANT: Do not lower machine with zero air pressure in system. Maintain 34 kPa to 55 kPa (0.3 bar to 0.5 bar) (5 psi to 8 psi) in system or air bags can kink. If air bag kinks, raise machine and pressurize the system until air bags straighten out.

   IMPORTANT: Do not operate if a pinched or unrolled air bag occurs. Lower system pressure until air bags can be rolled by hand. Roll air bag back over lower piston. Incremental lowering of machine is required to start air bag rolling over lower piston.

   NOTE: It is normal for system air pressure to drop when frame is raised and increase when frame is lowered.

   NOTE: Some additional down force on row units that follow in tractor tire tracks can be required. An extra single down force spring can be installed on these row units, without affecting other row units.

   
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   Properly Rolled Air Bag

   
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   Improperly Rolled Air Bag

   
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   A - Valve Stem

   With machine in planting position, apply shop air to valve stem (A) to preset down force to desired setting.

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2. 
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   A - Valve

   B - Manifold

   C - T-fitting

   D - Valve

   E - Fitting

   F - Toggle Switch

   If equipped with split rows, attach hose with white mark to fitting (E). Attach hose without white mark, for primary rows, to T-fitting (C). Turn valve (A) counter clockwise to allow compressor pressure to entire system. Turn valve (D) counter clockwise to allow system pressure to split rows, when equipped. Turn valve (D) clockwise to release pressure from split rows, when equipped. Turn valve (A) clockwise to release pressure from entire system.

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3. IMPORTANT: Do not leave compressor on while planting. Do not allow compressor to run more than 7 minutes. Allow 30 minutes for compressor to cool down before operating again. Use shop air to preset down force and use compressor for small in-field adjustments.

   NOTE: Power to compressor is linked to tractor ignition switch. Compressor cannot run when ignition switch is in “off” position.

   To increase system down force, turn compressor on using toggle switch (F) and open appropriate valves as described in preceding step. When desired setting is reached, turn compressor off.

4. Pressure drop in excess of 83 kPa (0.8 bar) (12 psi) in 10 hours is considered excessive and could indicate a fitting leak.

   NOTE: Spray soap and water on fittings. Bubbles appear when air is leaking.

   For excessive pressure drops, check all connections with soap and water in the following order:

   1. Threaded Compressor Fittings—If leaking, tighten or tape threads with thread tape and install fittings.

   2. Hose Compression Fittings—If leaking, push hose completely into coupler.

      If leak persists, first relieve system pressure, then simultaneously push in green compression ring and gently pull air line out of fitting. Cut hose tip off squarely, clean, and reinstall hose in coupler.

   3. Threaded Swivel On Row Unit Where Fitting Screws Into Top Of Air bag—If leaking, tighten fitting, or remove fitting, apply thread tape and reinstall fitting.