Aitchison SEEDMATIC PROFESSIONAL 8140, Manual, Page: 20 / 61

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HYDRAULIC FAN DRIVE
The AIRPRO has one hydraulic fan drive system; this hydraulic system has two
hydraulic motors controlled by two flow control valves.
One fan is used to deliver product from the seed hopper and the other fan is used to
deliver product from the fertiliser hopper.
The hydraulic motors require 10 to 22 l/m to run and should turn at about 2000 to
4500rpm.
This hydraulic system has been designed to be compatible with either open centre or
closed centre hydraulics; this is achieved by having a valve (tap) plumbed into the
hydraulic circuit.
Have this valve
closed
for “
Closed Centre
” systems or
open
for “
Open Centre
”
systems.
This system requires continuous oil flow. One PRIORITY hydraulic bank with the
lever locked on, (motor spool) setting.
It’s very important that the fans maintain a
constant speed especially when the seed drill is lifted for the headlands.
Hydraulic Motors set-up
System overview.
The tractor oil is fed into the 1
st
Flow Control Valve, some oil is used to drive the SEED
fan. The excess oil is then diverted to the 2
nd
Flow Control Valve, which is used to run
the FERTILISER fan, the oil is then returned back to the tractor.
The
CASE DRAIN hose (the hose with the female coupling) is used to drain any oil that
has sneaked pass the main seals in both hydraulic motors. This CASE DRAIN hose
needs to be connected to the tractor oil tank
without any restriction.
NOTE: If the case drain hose is pressurised or blocked sever damage
will occur