![background image](http://html1.mh-extra.com/html/bush-hog/ghm-1800-series/ghm-1800-series_operators-manual_2834694012.webp)
Breakaway pressure is regulated by the tension of
the latch springs (Figure 3-3). Spring length as
shipped from the factory is 4-1/8” and is satisfactory
for most conditions. Breakaway pressure can be
increased by turning spring retaining nuts clockwise
or decreased by turning counterclockwise. DO NOT
COLLAPSE SPRING TO LESS THAN 3-3/4” OR
SPRING WILL BECOME SOLID BEFORE LATCH
CAN TRIP.
Figure 3-3
Breakaway Latch Spring
4-1/8”
3-5 OPERATION
A. Perform BEFORE EACH USE maintenance
listed in paragraph 4-1.
B. Pin parking stand and transport latch in the
work position.
C. Start tractor. Set tractor 3-point hitch depth
control or install the optional check chain assembly
to stop with the horizontal main frame pivot approxi-
mately 20” from the ground. (Figure 2-4) Check
chain retainers should be installed onto tractor rear
casting using top link pin.
D. Lower cutter bar parallel to ground. Lower 3-
point hitch to work position. Place control valve for
cutter bar cylinder in “float” position.
TO AVOID SERIOUS INJURY OR DEATH:
STAY CLEAR OF ROTATING DRIVELINE.
DO NOT OPERATE WITHOUT
DRIVELINE SHIELDS IN PLACE AND IN
GOOD CONDITION.
TO AVOID SERIOUS INJURY OR DEATH:
STAND CLEAR OF ROTATING MOWER
BLADES UNTIL ALL MOTION HAS
STOPPED. TO AVOID ACCIDENTAL
FALL FROM TRACTOR AND POSSIBLE
INJURY FROM MOWER, IT IS RECOM-
MENDED THAT TRACTOR BE EQUIPPED
WITH ROLLOVER PROTECTIVE SYSTEM
(ROPS) AND THAT A SEAT BELT BE
USED FOR ALL MOWING OPERATIONS.
DANGER
DANGER
E. With tractor at idle speed, engage PTO drive.
Set tractor throttle for 540 PTO rpm for models GHM
700, GHM 800, and GHM 900 and 1000 PTO rpm
for models GHM 1800 and GHM 1900.
F. Place tractor in a gear that will give proper
speed for terrain and crop conditions , then begin
mowing. Tractor forward speed should be controlled
by gear selection, not engine speed. For maximum
efficiency, forward speed should allow mower to
maintain a constant maximum blade speed.
If tractor engine stalls, do not slip tractor clutch to
allow engine to regain speed as this will exert
tremendous strain on the driveline. When stalling
occurs,disengage PTO drive, move to a cut area,set
tractor throttle at idle, then re-engage PTO drive. If
stalling continues, use lower gear.
3-6 SWATH BOARD
The swath board is manufactured in the correct posi-
tion for most efficient operation. However, some
conditions may require that the swath board be
removed. To do this remove the bolt at the spring
assembly and remove the complete assembly.
DANGER
TO AVOID SERIOUS INJURY OR DEATH
FROM THROWN OBJECTS:
DO NOT OPERATE WITH CURTAIN
GUARD REMOVED. DO NOT OPERATE
WITHOUT CURTAIN GUARD IN GOOD
CONDITION OR REPAIR.
Figure 3-4 Swath Board Assembly
Swath Board Spring Assembly
Crop Divider
11