MacDon FD70 for Combine Operators - Manual (Page 175)

SECTION 10. MAINTENANCE AND SERVICING
Form 169006
173
Revision D
D
10.11.8 Sickle Drive Belts: Non-Timed
Drive
This section applies to single knife headers, and
40 FT and 45 FT double knife headers with
non-timed drives.
For double knife headers with timed drives, refer
to Section 10.11.9 Double Knife Drive Belts:
Timed Drive.
10.11.8.1 Tension Adjustment
IMPORTANT
To prolong belt and drive life, do not
over-tighten belt.
CAUTION
To avoid personal injury, before servicing
machine or opening drive covers, follow
procedures in Section 10.1 PREPARATION
FOR SERVICING.
a. Open endshield.
b. Loosen two bolts (A) on sickle drive mounting
bracket.
c. Turn adjuster bolt (B) to move drive motor until a
force of 20 lbf (80 N) deflects belt (C) 3/4 in.
(18 mm) at mid-span.
d. Tighten jam-nut at (B) and bolts (A) on drive
mounting bracket.
e. Re-adjust tension of a new belt after a short
run-in period, (about 5 hours).
10.11.8.2 Removal
a. Loosen sickle drive belt using procedure in
previous section so that belt (C) can be slipped
off drive pulley.
b. Remove bolt in plate
(D) in endsheet at
wobble box, and
remove plate.
This provides
clearance between
pulley and endsheet
for the belt when it is
removed.
c. Slip belt over and behind wobble box pulley (E),
and remove belt. Utilize the notch in pulley to
assist in removing the belt.
10.11.8.3 Installation
a. Route sickle drive belt (C) around wobble box
pulley (E) and sickle drive pulley. Utilize the notch
in the pulley to assist in installing the belt.
NOTE
When installing new belt, never pry belt
over pulley. Be sure drive motor is fully
forward, and then tension the belt.
b. Tighten belt. Refer to Section 10.11.8.1 Tension
Adjustment (in opposite column).
c. Check clearance between belt (C) and belt guide
(F). The measurement should be 0.04 in.
(1 mm). Adjust as follows:
1. Ensure belt is properly tensioned.
2. Loosen bolts (G), and adjust position of guide
(F) as required.
3. Tighten bolts.
d. Re-install plate (D), and secure with bolt and nut.
e. Close endshield.
LH SHOWN - RH OPPOSITE
B
A
C
LH SHOWN - RH OPPOSITE
E
C
F
G