horsch Pronto 3 - 6 DC Operating Instructions Manual page 78

Maintenance
The function and operability of fine seed rotors
must be checked every day.
There should be no gap between the cell
¾
discs. If the gap is too big, additional shims
must be added.
The cell discs must be light turning. Dressing
¾
or similar materials must not block cell discs
or bearings.
The safety clips must be in place and correctly
¾
assembled to avoid the formation of a gap.
Assembly note
To prevent seed from entering between cell
discs and spacers the cell discs and spacers
are installed with zero clearance shims.
Rotor for fine seeds
The spacers are equipped with bearings.
Depending on the manufacturing tolerance
shims are added to avoid any friction between
cell discs and spacers.
After the assembly of all parts the remaining gap
to the lock washer is filled up with shims.
Finally push the lock washer into place.
With the rotor correctly assembled the cell discs
between the spacers can just be freely turned.
The parts must not rub against each other. The
clearance should therefore be as little as possible.
When checking against a light source the gap
should just be visible.
74
Function test
After installing a new rotor its function and con-
centricity must be checked.
For this purpose switch on the rotor as described
in the section "Calibration test".
The drive motor must run "smoothly". No stiff
¾
points should be recognizable.
Check the motor for smooth running. Untrue
¾
running causes inaccurate metering and may
overload the motor.
If possible locate the stiff point.
¾
Rework damaged parts (by machining ...) or
¾
replace.
Loosen the screws on the side covers for drive
¾
motor and rotor bearing and realign the side
covers to release tension.
If the drive shaft has been bent, realign or
¾
replace it.
Remove any foreign bodies that may have
¾
been jammed between rotor and housing.
If dust or dressing in the roller has entered
¾
between cell discs and spacers dismantle and
clean the roller.