Checking And Adjusting Non-Timed Knife Drive Belt Tension - MacDon FFT FD75 Assembly Instructions Manual

4.6 Checking and Adjusting Non-Timed Knife Drive Belt Tension

This procedure applies to single and double knife headers with non-timed knife drives.
1. Shut down combine and remove key from ignition.
2. Open endshield(s). Refer to
page 83.
NOTE:
The knife drive is identical on both sides of the header
for double knife headers.
3. Apply a force of 90 N (20 lbf) to mid-span (A) of belt.
The belt should deflect 18 mm (3/4 in.). If necessary,
adjust tension as per the following steps.
IMPORTANT:
To prolong belt and drive life, do NOT over-tighten belt.
4. Loosen two bolts (A) that secure motor assembly to
header endsheet.
5. Turn adjuster bolt (B) as required to move drive motor
to achieve belt deflection as per above. Tighten
bolts (A).
6. Ensure that clearance between belt (C) and belt
guide (E) is 1 mm (1/32 in.).
7. Loosen three bolts (D), and adjust position of guide (E)
as required.
8. Tighten bolts (D).
9. Close endshield(s). Refer to
page 87.
NOTE:
Readjust tension of a new belt after a five hour run-in
period.
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PERFORMING PREDELIVERY CHECKS
3.4.5 Opening Endshield,
3.4.9 Closing Endshield,
Figure 4.7: Knife Drive (Left Shown – Right
Opposite)
Figure 4.8: Knife Drive (Left Shown – Right
Opposite)
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Revision A