Gason 7370 Series, Operator'S Manual, Page: 18 / 84

Operation
Page 14
06/07
3. Read density from the scale in tonnes per
cubic meter (top scale).
Changing Gearbox Ratio
The feed chain spreader is equipped
with a ground driven 3-speed gearbox. The
gearbox has been designed to offer a large
variation in feed chain speeds to cope with
the low and high application rates.
Fig. G13 Ground driven Gearbox.
To change between ratios you will
need to remove the clip from the inside face
of the top shaft (opposite the jockey wheel)
on the gearbox.
Fig. G14 Selector pin and clip.
Once removed, the selector pin can be
moved in to select low ratio, centralised to
select high ratio or fully withdrawn to drive
medium ratio. It will be necessary to either
rock the jockey wheel backwards and
forwards or to slowly turn the jockey wheel to
allow the internal drive key to slide from one
gear to the next.
Fig. G15 Selector pin central.
Once the correct ratio has been chosen
replace the retaining clip to lock the selector
pin into position.
Note: Always use the lowest gear
possible at the highest door setting to
minimise the loading on the gearbox.
Caution:
The rear door should never be
operated in the closed position with
fertiliser that can pack. On some fertilisers
it should not be operated with less than
40mm of gap as packing will occur and the
chain will jam.
IMPORTANT: Grease gearbox before
using. Ensure that the gear selector
pin has been fully pushed in before greasing
the nipple at the end of the pin.
Refer to the daily maintenance section on
page 20 for further information.