Vacuum system
Vacuum blower assembly
Vacuum blower shown on 1795
Vacuum is created by a hydraulically driven vacuum blower assembly mounted on the planter frame. The vacuum blower requires a tractor with a closed-center hydraulic system and a separate selective control valve (SCV). For tractors with open-center hydraulic system, a vacuum 540-rpm or 1000-rpm power take-off (PTO) driven hydraulic pump system is available. PTO pumps offered from the factory are limited to 15-row applications or less.
Different vacuum levels are required depending on the crop being planted. A hydraulic control valve lets the operator regulate vacuum blower speed, changing the vacuum level. On late-model John Deere tractors, vacuum levels are set from the tractor seat using the SCV controls. The control valve is not needed in those applications. At full flow, the system flows up to 18.9 L/min (5 gpm) per motor.
Convenient vacuum gauges located on the planter hitch give a visual indication of the vacuum level. When using a SeedStar™ monitor, the vacuum level can be displayed on the monitor. Consult the vacuum metering seed charts in the operator's manual for initial vacuum setting recommendations.
Vacuum meter case drain
Case drain coupler 7000 Series Tractor
All planters with vacuum metering systems have case drain motors on the vacuum blowers. Case drain lines will have a flush-face case drain coupler on the planter and will require a corresponding flush-face case drain coupler on the tractor. The flush-face coupler simplifies implement attachment by allowing operators to easily identify the case drain. The unique hose tip is unable to connect to another coupler on the tractor, ensuring the correct setup.
It is important to connect this case drain hose to prevent the continuous and complete draining of hydraulic fluid due to the relief feature that opens the coupler when the pressure reaches 68.9 kPa (10 psi). This relief feature is designed to protect the motor shaft seal if for any reason the case drain hose was not connected to the tractor. The flush-face hose tips have less back pressure than ISO case drain tips, and the flat surface makes these couplers easy to clean, providing less chance for contamination.
The case drain line is also used with all Central Commodity System (CCS™) fan motors.