MacDon 4000 Mower Conditioner - Manual (Page 50)

50
MAINTENANCE/SERVICE
KNIFE AND KNIFE DRIVE (continued)
Guards
Check daily that guards are aligned to obtain
proper shear cut between knife section and guard.
Knife sections should contact shear surface of
each guard.
Align guards with the guard-straightening tool
provided as shown:
To bend guard tips up, position tool as shown at
(B) and pull up.
To bend tips down, position tool as at (C) and push
down.
NOTE: Tool is stored in toolbox at left end of main
frame.
TIP: If trouble is encountered cutting tangled, but
easy to cut material (canola, peas, grain) replace
guards with stub guards and install a sickle hold-
down on every guard. If material is tough to cut,
install stub guards with top guard and adjuster
plate from the MacDon 930 Series "Grass Seed
Special" Headers. A stub guard kit for the 4000
Mower Conditioner is available from your dealer.
Excessive Breakage
Excessive breakage of knife sections and guards
can be controlled by several factors. See "Cutting
Height", "Cutterbar Angle" and "Header Flotation"
in Operation section for recommendations.
Knife Clips
Check daily that knife clips are set to prevent knife
sections from lifting off guards but still permit knife
to slide without binding. Set clips after guards are
aligned.
To set clips:
1.
Use tool (A) as shown, butting flattened end
against front edge of clip. Strike the end of the
tool with a heavy hammer. This allows
adjustment of clip arch (E) without "pinching"
knife. Clearance from clip to knife section
should be 0.020 inch (0.5 mm).
2. After adjusting all clips, run knife at a low
engine speed and listen for noise due to
insufficient clearance. Re-adjust as necessary
by placing a 0.020 inch (0.5 mm) shim
between clip and section, then striking the clip
arch (E) with a hammer.
BENDING GUARD TIPS UP
B
BENDING GUARD TIPS DOWN
C
SETTING KNIFE CLIPS
A
E