Backlapping Procedure; Height-Of-Cut Adjustment - Textron Jacobsen InCommand PGM 22 Technical/Repair Manual

CUTTING UNIT
5. Adjust the trailing edge of the reel in the same
manner, then recheck the adjustment at the leading
edge.
6. Tighten nut (2). Recheck adjustment.
7. When the reel and bedknife are properly adjusted,
the reel will spin freely and will cut a piece of
newspaper along the full length of the reel when the
paper is held at 90° to the bedknife.

Backlapping Procedure

See Figure 8-5.
Whenever a reel and bedknife have been ground, or a
new reel and/or bedknife have been installed, the
assembled reel should be backlapped using an
electric-powered bench lapper.
Required Tools and Materials
• Lapping Compound (150 Grit)
• Long-Handled Brush
• 3/8-24 Bolt (The length will vary depending on the
lapping machine being used. When installed, the
bolt must be threaded fully into the reel shaft, yet
have enough length to engage the lapping
machine.)
1. Check for damage to the bedknife and reel blades.
(See "Reel and Bedknife Inspection" on page 8-13.)
2. Determine if backlapping or grinding will restore the
proper cutting edge.
3. For optimum performance, use a bedknife grinder to
touch up the blade, then reassemble and adjust the
bedknife to the reel. (See "Bedknife-to-Reel
Adjustment" on page 8-13.)
4. Move fuel shutoff lever to the OFF position to prevent
fuel leaking into the combustion chamber. (Refer to
8
engine manufacturer's manual.)
5. Disengage reel clutch and tip machine back to rest
on the handle. Do not leave the mower tipped back
for an extended length of time or oil may migrate into
the combustion chamber.
8-14
Figure 8-5
6. Remove shaft cover (1) and gasket from left side of
reel. Assemble a 3/8-24 bolt and lock nut to the end
of the shaft and attach to lapping machine.
a. Apply lapping compound with a long-handled
brush along the entire length of the reel (150 grit
or finer is recommended).
b. Continue lapping and at the same time make a
fine adjustment on the reel and bedknife until
there is a uniform clearance along the full length
of the cutting edges.
7. Carefully and thoroughly remove all lapping
compound from reel and bedknife before running the
reel in forward direction.

Height-of-Cut Adjustment

See Figure 8-6.
Required Tools and Materials
Height-of-Cut Gauge Bar (Jacobsen P/N 158568)
NOTE
Make sure the bedknife is properly adjusted before
adjusting the cutting height. (See "Bedknife-to-Reel
Adjustment" on page 8-13.)
1. Park the mower safely. (See "Park Mower Safely" on
page 1-6.)
2. Tip mower back on traction drum or tires. Do not
leave the mower tipped back for an extended length
of time or oil may migrate into the combustion
chamber.
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TN0031
4157082 First Edition