Textron Jacobsen Super LF 1880 Fairway Mower with ROPS, Инструкции по обслуживанию и ремонту

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ATTACHMENTS
12E-11
SECTION 12E. SHARPENING REELS AND BEDKNIVES
GENERAL
When a mower reel rotates, it cuts off the tops of grass
blades which are lifted and held erect by a flat station-
ary bedknife. A properly sharpened and adjusted reel
mower cuts grass cleanly and with minimum effort. A
poorly sharpened reel mower may tear, shred, pull, or
leave grass uncut and usually requires more effort than
a properly sharpened reel mower.
If a mower cuts in streaks, strips, or ragged areas,
chances are the cutting edges are not properly
adjusted or they need sharpening.
Inspect the blades and bedknife for nicks, gouges, high
or low wear areas, or other signs of damage or uneven
wear. However, consider these other factors that can
contribute to poor cutting performance before grinding
and lapping the cutting edges:
Improper Adjustment
The perfect adjustment of the blade and bedknife is a
light contact without drag or resistance to rotation.
Owing to the manufacturing clearances required in
bearings and other mating components, the bedknife
should be set close enough to the reel so the mower
cuts a strip of newspaper clear across the blades with-
out metal-to-metal contact between the bedknife and
the reel blades.
Damaged Mower Parts
A gouged bedknife, nicked reel blade, or wavy bedknife
and reel as well as a bent frame, bent bedknife ears,
broken welds, worn bearings, or loose attaching hard-
ware can cause poor quality cutting. Solve such prob-
lems by making sure the bedknife mounting screws
and other hardware are secure and by replacing parts
if damage cannot by corrected by grinding and lapping.
Bad Bearings, End Play, or Radial Play
Check for play in the reel bearings. The mower has self
adjusting bearings. Excessive play indicates worn
bearings or weak tensioning spring. Repair as
described in Section 12F.
Reel blades and a bedknife that are slightly dull or have
minor nicks or high spots can be honed quickly and
easily by lapping. Both grinding and lapping are
required when more severe wear or damage exists. If a
wave has developed in the bedknife, lapping will not
solve the problem and the mower reel and bedknife
must be replaced.
A reel worn or incorrectly ground to a conical shape
instead of a cylindrical shape will cause a wavy bed-
knife (Figure 12E-1).
Figure 12E-1. Reel Wear
CAUTION
Never grind and lap a reel in the frame until all end
play and radial play are eliminated. End or radial
play will cause uneven grinding.
12E