38
MAINTENANCE
CAUTION
If the blade is allowed to wear, a slot will
form between the sail and flat part of the
blade (Fig. 61C)). Part of the blade may
eventually break off and be thrown from
under the housing, possibly resulting in
serious injury to yourself or bystanders.
3.
Examine cutting edges of all blades. Sharpen
cutting edges that are dull or nicked. To assure
sharpness, sharpen only the top side of the cutting
edge while maintaining the original cutting angle
(Fig. 62). If the same amount of metal is removed from
both cutting edges, the blade will remain balanced.
Figure 62
SHARPEN AT THIS
ANGLE ONLY
END VIEW
4.
To check blade for being straight and parallel,
remove from cutting unit. Lay blade on level surface
and check its ends. Blade ends must be slightly lower
than blade center and cutting edge lower than heel of
the blade. If so, it will produce good quality-of-cut
and require minimal engine power to turn. By contrast,
a blade with ends higher than blade center, or with
cutting edge higher than the blade heel, is warped or
bent and must be replaced.
5.
When re-assembling, make sure blade sail is
facing up. Torque the blade bolt to 140-165 ft-lb.
INSPECTING AND ADJUSTING CUTTING
UNIT BELT TENSION
IMPORTANT
: After first ten hours of operation, check
new belts for proper tension; thereafter, check tension
every 50 hours.
Front Cutting Unit -
Note:
Belts for wing unit spindles are tensioned by
spring loaded idlers and normally do not require
tensioning.
1.
Position machine on level surface, lower cutting
unit to shop floor, engage parking brake, shut engine
off and remove key from ignition switch.
2.
Remove deck covers.
Figure 63
1. Compression Spring and Tension Plate
2. Wing Unit Drive Belt
3. Gear Box Plate
4. Center Drive Belt
5. Lift Arm
1
2
3
4
5
3.
Note position of shoulder bolts in slots in tension
plate. Optimum belt tension will be maintained when
the flanges on the shoulder bolts are 1/8 in. (3 mm)
from the pulley ends of the slots (Fig. 64). If the
shoulder bolt flanges are more than 3/8 in. (9 mm) from
the pulley end of the slots, an adjustment should be
made.
Figure 64
1. Tension Plate 2. Shoulder Bolts
1
2
1/8"
(3 mm)
4.
To adjust, loosen jam nuts (Fig. 65) and extend
tension arm until the shoulder bolt flanges are within
1/8 in. (3 mm) of the pulley end of the slots (Fig. 64).
Note:
When the shoulder bolt flanges are positioned
1/8 in. (3 mm) from the pulley end of the slots, the
length of the compression spring (Fig. 63) will be
approximately 5 in. (127 mm).
5.
Tighten jam nuts to secure adjustment. Replace
covers.
